# IOI / ioi2026 > Source: Benchize (https://benchize.com) — https://benchize.com/benchmarks/vals-ai%3Aioi%3Aioi2026. When citing or reusing this content, credit "Benchize" and link to https://benchize.com/benchmarks/vals-ai%3Aioi%3Aioi2026. Based on the International Olympiad in Informatics Canonical URL: https://benchize.com/benchmarks/vals-ai%3Aioi%3Aioi2026 Last updated: Wed, 21 Oct 2026 18:05:10 GMT Reproduction and quotation must name Benchize, link to the canonical HTML URL, and retain individual source citations. Conquered Based on the International Olympiad in Informatics Coding · Models tested: 29 · Score publishers: Vals AI ## Model results | # | Model | Score | ± | Cost | Latency | | | --- | --- | --- | --- | --- | --- | --- | | 1 | [GPT-5.6 Terra](https://benchize.com/models/gpt-5-6-terra-max.md)Max | 100% | SE ±0 pp | $7.2 | 5,273.93source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 100 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 7.20047 \| USD \| per_test \| Lower is better \| \| `latency` \| 5273.93 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±0 pp sourcePopulation 44 stderr 0 tokenTotals {"cache_read_tokens":3982511,"cache_write_tokens":341800,"input_tokens":4324713,"output_tokens":165665,"reasoning_tokens":136111} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-5.6-terra Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-5.6-terra` | | | | | | | | 1 | [GPT-6 Astra](https://benchize.com/models/gpt-6-astra-max.md)Max | 100% | SE ±0 pp | $11.01 | 3,058.73source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 100 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 11.012171 \| USD \| per_test \| Lower is better \| \| `latency` \| 3058.726 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±0 pp sourcePopulation 44 stderr 0 tokenTotals {"cache_read_tokens":1626094,"cache_write_tokens":188984,"input_tokens":1815327,"output_tokens":78886,"reasoning_tokens":47036} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-6-astra Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-6-astra` | | | | | | | | 1 | [Gemini 4 Argon](https://benchize.com/models/gemini-4-argon-high.md)High | 100% | SE ±0 pp | $10.72 | 2,640.73source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 100 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 10.720193 \| USD \| per_test \| Lower is better \| \| `latency` \| 2640.726 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 262144 provider Google reasoning Not reported Reasoning effort high Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±0 pp sourcePopulation 44 stderr 0 tokenTotals {"cache_read_tokens":114910273,"cache_write_tokens":0,"input_tokens":119965969,"output_tokens":1055816,"reasoning_tokens":778031} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label google/gemini-4-argon Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/google~1gemini-4-argon` | | | | | | | | 4 | [GPT-6.1 Sol](https://benchize.com/models/gpt-6-1-sol-max.md)Max | 90.67% | SE ±8.52 pp | $2.19 | 3,151.77source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 90.667 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 2.190169 \| USD \| per_test \| Lower is better \| \| `latency` \| 3151.77 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±8.52 pp sourcePopulation 44 stderr 8.52 tokenTotals {"cache_read_tokens":1851053,"cache_write_tokens":237506,"input_tokens":2088802,"output_tokens":104447,"reasoning_tokens":76626} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-6.1-sol Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-6.1-sol` | | | | | | | | 5 | [Claude Opus 5.5](https://benchize.com/models/claude-opus-5-5-max.md)Max | 85.17% | SE ±13.54 pp | $9.05 | 1,810.99source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 85.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 9.050024 \| USD \| per_test \| Lower is better \| \| `latency` \| 1810.988 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±13.54 pp sourcePopulation 44 stderr 13.541 tokenTotals {"cache_read_tokens":47448899,"cache_write_tokens":1890851,"input_tokens":49340144,"output_tokens":1260558,"reasoning_tokens":1097168} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-opus-5-5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-opus-5-5` | | | | | | | | 5 | [Claude Fable 5.1](https://benchize.com/models/claude-fable-5-1-max.md)Max | 85.17% | SE ±13.54 pp | $12.94 | 2,195.42source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 85.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 12.937402 \| USD \| per_test \| Lower is better \| \| `latency` \| 2195.415 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±13.54 pp sourcePopulation 44 stderr 13.541 tokenTotals {"cache_read_tokens":42784481,"cache_write_tokens":1782351,"input_tokens":44567310,"output_tokens":1121365,"reasoning_tokens":983228} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-fable-5-1 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-fable-5-1` | | | | | | | | 5 | [GPT-5.6 Sol](https://benchize.com/models/gpt-5-6-sol-max.md)Max | 85.17% | SE ±13.54 pp | $8.33 | 4,276.06source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 85.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 8.32603 \| USD \| per_test \| Lower is better \| \| `latency` \| 4276.062 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±13.54 pp sourcePopulation 44 stderr 13.541 tokenTotals {"cache_read_tokens":4003687,"cache_write_tokens":290401,"input_tokens":4294481,"output_tokens":125409,"reasoning_tokens":87619} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-5.6-sol Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-5.6-sol` | | | | | | | | 8 | [Claude Sonnet 5.5](https://benchize.com/models/claude-sonnet-5-5-max.md)Max | 75.83% | SE ±14.49 pp | $12.19 | 3,613.2source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 75.833 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 12.192486 \| USD \| per_test \| Lower is better \| \| `latency` \| 3613.203 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±14.49 pp sourcePopulation 44 stderr 14.485 tokenTotals {"cache_read_tokens":210420244,"cache_write_tokens":4278377,"input_tokens":214699529,"output_tokens":2037311,"reasoning_tokens":1712396} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-sonnet-5-5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-sonnet-5-5` | | | | | | | | 9 | [GPT-6 Sol](https://benchize.com/models/gpt-6-sol-max.md)Max | 68.5% | SE ±18.23 pp | $2.71 | 1,675.84source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 68.5 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 2.708373 \| USD \| per_test \| Lower is better \| \| `latency` \| 1675.844 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±18.23 pp sourcePopulation 44 stderr 18.233 tokenTotals {"cache_read_tokens":3583111,"cache_write_tokens":266327,"input_tokens":3849795,"output_tokens":158823,"reasoning_tokens":125568} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-6-sol Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-6-sol` | | | | | | | | 10 | [Claude Opus 5](https://benchize.com/models/claude-opus-5-max.md)Max | 65.83% | SE ±14.58 pp | $23.57 | 4,315.54source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 65.833 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 23.568374 \| USD \| per_test \| Lower is better \| \| `latency` \| 4315.537 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±14.58 pp sourcePopulation 44 stderr 14.58 tokenTotals {"cache_read_tokens":137949530,"cache_write_tokens":4373778,"input_tokens":142324076,"output_tokens":1803821,"reasoning_tokens":1472640} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-opus-5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-opus-5` | | | | | | | | 11 | [Gemini 3.7 Flash](https://benchize.com/models/gemini-3-7-flash-high.md)High | 60.83% | SE ±16.63 pp | $5.39 | 2,475.47source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 60.833 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 5.392624 \| USD \| per_test \| Lower is better \| \| `latency` \| 2475.465 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 65536 provider Google reasoning Not reported Reasoning effort high Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±16.63 pp sourcePopulation 44 stderr 16.627 tokenTotals {"cache_read_tokens":60262017,"cache_write_tokens":0,"input_tokens":70967304,"output_tokens":967801,"reasoning_tokens":429792} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label google/gemini-3.7-flash Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/google~1gemini-3.7-flash` | | | | | | | | 12 | [Muse Wonder](https://benchize.com/models/muse-wonder-max.md)Max | 58.5% | SE ±17.63 pp | $4.82 | 1,628.11source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 58.5 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 4.824085 \| USD \| per_test \| Lower is better \| \| `latency` \| 1628.106 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 131072 provider Meta reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±17.63 pp sourcePopulation 44 stderr 17.628 tokenTotals {"cache_read_tokens":53451120,"cache_write_tokens":0,"input_tokens":54360961,"output_tokens":725414,"reasoning_tokens":588305} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label meta/muse-wonder Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/meta~1muse-wonder` | | | | | | | | 13 | [GPT-6 Luna](https://benchize.com/models/gpt-6-luna-max.md)Max | 58.33% | SE ±17.7 pp | $0.16 | 1,839.81source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 58.333 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.162408 \| USD \| per_test \| Lower is better \| \| `latency` \| 1839.807 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±17.7 pp sourcePopulation 44 stderr 17.704 tokenTotals {"cache_read_tokens":17849572,"cache_write_tokens":1025842,"input_tokens":18875849,"output_tokens":785789,"reasoning_tokens":740012} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-6-luna Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-6-luna` | | | | | | | | 14 | [DeepSeek V4 Pro 0813](https://benchize.com/models/deepseek-v4-pro-0813-max.md)Max | 56.33% | SE ±18.04 pp | $1.86 | 2,874.48source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 56.333 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 1.860156 \| USD \| per_test \| Lower is better \| \| `latency` \| 2874.481 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 384000 provider DeepSeek reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±18.04 pp sourcePopulation 44 stderr 18.038 tokenTotals {"cache_read_tokens":99732352,"cache_write_tokens":0,"input_tokens":100059606,"output_tokens":1594019,"reasoning_tokens":1391854} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label deepseek/deepseek-v4-pro-0813 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/deepseek~1deepseek-v4-pro-0813` | | | | | | | | 15 | [Gemini 3.8 Flash](https://benchize.com/models/gemini-3-8-flash-high.md)High | 53.83% | SE ±14.63 pp | $4.17 | 945.16source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 53.833 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 4.171352 \| USD \| per_test \| Lower is better \| \| `latency` \| 945.157 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 65536 provider Google reasoning Not reported Reasoning effort high Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±14.63 pp sourcePopulation 44 stderr 14.628 tokenTotals {"cache_read_tokens":77731817,"cache_write_tokens":0,"input_tokens":81572346,"output_tokens":1014339,"reasoning_tokens":633191} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label google/gemini-3.8-flash Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/google~1gemini-3.8-flash` | | | | | | | | 16 | [Gemini 3.1 Pro Preview](https://benchize.com/models/gemini-3-1-pro-preview-high.md)High | 53.17% | SE ±19.21 pp | $1.13 | 665.21source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 53.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 1.132771 \| USD \| per_test \| Lower is better \| \| `latency` \| 665.213 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 65536 provider Google reasoning Not reported Reasoning effort high Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±19.21 pp sourcePopulation 44 stderr 19.207 tokenTotals {"cache_read_tokens":5902523,"cache_write_tokens":0,"input_tokens":6937662,"output_tokens":295487,"reasoning_tokens":246940} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label google/gemini-3.1-pro-preview Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/google~1gemini-3.1-pro-preview` | | | | | | | | 17 | [GPT-5.6 Luna](https://benchize.com/models/gpt-5-6-luna-max.md)Max | 50.5% | SE ±16.77 pp | $0.51 | 3,762.8source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 50.5 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.506723 \| USD \| per_test \| Lower is better \| \| `latency` \| 3762.795 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±16.77 pp sourcePopulation 44 stderr 16.768 tokenTotals {"cache_read_tokens":16531904,"cache_write_tokens":985765,"input_tokens":17518434,"output_tokens":487964,"reasoning_tokens":399941} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-5.6-luna Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-5.6-luna` | | | | | | | | 18 | [DeepSeek V4.1 Flash](https://benchize.com/models/deepseek-v4-1-flash-high.md)High | 43% | SE ±16.93 pp | $0.22 | 782.97source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 43 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.222012 \| USD \| per_test \| Lower is better \| \| `latency` \| 782.974 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 384000 provider DeepSeek reasoning Not reported Reasoning effort high Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±16.93 pp sourcePopulation 44 stderr 16.931 tokenTotals {"cache_read_tokens":38204416,"cache_write_tokens":0,"input_tokens":38321706,"output_tokens":884107,"reasoning_tokens":775032} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label deepseek/deepseek-v4.1-flash Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/deepseek~1deepseek-v4.1-flash` | | | | | | | | 19 | [Claude Haiku 5.5](https://benchize.com/models/claude-haiku-5-5-max.md)Max | 42.83% | SE ±17.28 pp | $0.67 | 648.9source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 42.833 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.667076 \| USD \| per_test \| Lower is better \| \| `latency` \| 648.896 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±17.28 pp sourcePopulation 44 stderr 17.279 tokenTotals {"cache_read_tokens":24821525,"cache_write_tokens":1587464,"input_tokens":26409255,"output_tokens":1298902,"reasoning_tokens":1198622} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-haiku-5-5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-haiku-5-5` | | | | | | | | 20 | [Claude Sonnet 5](https://benchize.com/models/claude-sonnet-5-max.md)Max | 42.5% | SE ±17.4 pp | $11.61 | 2,471.17source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 42.5 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 11.612894 \| USD \| per_test \| Lower is better \| \| `latency` \| 2471.166 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort max harness Not reported maxOutputTokens 128000 provider Anthropic reasoning Not reported Reasoning effort max Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±17.4 pp sourcePopulation 44 stderr 17.4 tokenTotals {"cache_read_tokens":221593575,"cache_write_tokens":3223527,"input_tokens":224818214,"output_tokens":1729761,"reasoning_tokens":1465902} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label anthropic/claude-sonnet-5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/anthropic~1claude-sonnet-5` | | | | | | | | 21 | [Muse Spark 1.3](https://benchize.com/models/muse-spark-1-3-xhigh.md)Extra high | 42.33% | SE ±16.68 pp | $1.6 | 1,348.52source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 42.333 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 1.599779 \| USD \| per_test \| Lower is better \| \| `latency` \| 1348.515 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 131072 provider Meta reasoning Not reported Reasoning effort xhigh Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±16.68 pp sourcePopulation 44 stderr 16.681 tokenTotals {"cache_read_tokens":16091922,"cache_write_tokens":0,"input_tokens":17062093,"output_tokens":1388724,"reasoning_tokens":1255148} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label meta/muse_spark_1_3 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/meta~1muse_spark_1_3` | | | | | | | | 22 | [GPT-5.3 Codex](https://benchize.com/models/gpt-5-3-codex-xhigh.md)Extra high | 41.67% | SE ±12.36 pp | $2.76 | 1,436.98source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 41.667 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 2.758885 \| USD \| per_test \| Lower is better \| \| `latency` \| 1436.984 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider OpenAI reasoning Not reported Reasoning effort xhigh Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±12.36 pp sourcePopulation 44 stderr 12.355 tokenTotals {"cache_read_tokens":30763008,"cache_write_tokens":0,"input_tokens":31929158,"output_tokens":652073,"reasoning_tokens":484527} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label openai/gpt-5.3-codex Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/openai~1gpt-5.3-codex` | | | | | | | | 23 | [MiMo-V2.6-Flash](https://benchize.com/models/mimo-v2-6-flash.md) | 38.33% | SE ±17.91 pp | $0.14 | 5,489.12source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 38.333 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.142214 \| USD \| per_test \| Lower is better \| \| `latency` \| 5489.124 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider Xiaomi reasoning Not reported Reasoning effort unknown Temperature 1 topP 0.95 verbosity Not reported ### Reported statistics Uncertainty Standard error: ±17.91 pp sourcePopulation 44 stderr 17.908 tokenTotals {"cache_read_tokens":55639616,"cache_write_tokens":0,"input_tokens":57211515,"output_tokens":1064149,"reasoning_tokens":958931} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label xiaomi/mimo-v2.6-flash Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/xiaomi~1mimo-v2.6-flash` | | | | | | | | 24 | [Step 5 Preview](https://benchize.com/models/step-5-preview.md) | 37.67% | SE ±18.13 pp | $1.65 | 4,001.48source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 37.667 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 1.648748 \| USD \| per_test \| Lower is better \| \| `latency` \| 4001.475 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 1024000 provider Stepfun reasoning Not reported Reasoning effort unknown Temperature 1 topP 0.95 verbosity Not reported ### Reported statistics Uncertainty Standard error: ±18.13 pp sourcePopulation 44 stderr 18.13 tokenTotals {"cache_read_tokens":68157696,"cache_write_tokens":0,"input_tokens":70080870,"output_tokens":1326129,"reasoning_tokens":0} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label stepfun/step-5-preview Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/stepfun~1step-5-preview` | | | | | | | | 25 | [DeepSeek V4 Flash 0731](https://benchize.com/models/deepseek-v4-flash-0731-high.md)High | 36% | SE ±18.53 pp | $0.39 | 2,035.88source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 36 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.3907 \| USD \| per_test \| Lower is better \| \| `latency` \| 2035.883 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 256000 provider DeepSeek reasoning Not reported Reasoning effort high Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±18.53 pp sourcePopulation 44 stderr 18.529 tokenTotals {"cache_read_tokens":54688896,"cache_write_tokens":0,"input_tokens":55058963,"output_tokens":1064584,"reasoning_tokens":920044} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label deepseek/deepseek-v4-flash-0731 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/deepseek~1deepseek-v4-flash-0731` | | | | | | | | 26 | [MiMo-V2.6-Pro](https://benchize.com/models/mimo-v2-6-pro.md) | 35.17% | SE ±18.78 pp | $0.56 | 5,457.88source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 35.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.564938 \| USD \| per_test \| Lower is better \| \| `latency` \| 5457.878 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 128000 provider Xiaomi reasoning Not reported Reasoning effort unknown Temperature 1 topP 0.95 verbosity Not reported ### Reported statistics Uncertainty Standard error: ±18.78 pp sourcePopulation 44 stderr 18.783 tokenTotals {"cache_read_tokens":24233472,"cache_write_tokens":0,"input_tokens":26507616,"output_tokens":2049508,"reasoning_tokens":1997010} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label xiaomi/mimo-v2.6-pro Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/xiaomi~1mimo-v2.6-pro` | | | | | | | | 27 | [Gemini 3.6 Flash](https://benchize.com/models/gemini-3-6-flash-high.md)High | 23.67% | SE ±14.01 pp | $19.6 | 6,748.72source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 23.667 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 19.595118 \| USD \| per_test \| Lower is better \| \| `latency` \| 6748.715 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 65536 provider Google reasoning Not reported Reasoning effort high Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±14.01 pp sourcePopulation 44 stderr 14.009 tokenTotals {"cache_read_tokens":563379714,"cache_write_tokens":0,"input_tokens":576020501,"output_tokens":1880343,"reasoning_tokens":668883} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label google/gemini-3.6-flash Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/google~1gemini-3.6-flash` | | | | | | | | 28 | [Muse Spark 1.2](https://benchize.com/models/muse-spark-1-2-xhigh.md)Extra high | 20.17% | SE ±14.74 pp | $1.69 | 1,264.23source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 20.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 1.688722 \| USD \| per_test \| Lower is better \| \| `latency` \| 1264.229 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 131072 provider Meta reasoning Not reported Reasoning effort xhigh Temperature 1 topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±14.74 pp sourcePopulation 44 stderr 14.739 tokenTotals {"cache_read_tokens":31582544,"cache_write_tokens":0,"input_tokens":32845457,"output_tokens":880077,"reasoning_tokens":663527} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label meta/muse_spark_1_2 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/meta~1muse_spark_1_2` | | | | | | | | 29 | [Mercury 2.5](https://benchize.com/models/mercury-2-5-high.md)High | 1.17% | SE ±1.07 pp | $0.16 | 285.71source duration | | | ### Original source values \| Metric \| Value \| Unit \| Scope \| Direction \| \| --- \| --- \| --- \| --- \| --- \| \| `accuracy` \| 1.167 \| percent \| reported \| Higher is better \| \| `cost_per_test` \| 0.162773 \| USD \| per_test \| Lower is better \| \| `latency` \| 285.705 \| source_duration \| reported_duration \| Lower is better \| ### Configuration computeEffort Not reported harness Not reported maxOutputTokens 65536 provider Inception reasoning Not reported Reasoning effort high Temperature Not reported topP Not reported verbosity Not reported ### Reported statistics Uncertainty Standard error: ±1.07 pp sourcePopulation 44 stderr 1.065 tokenTotals {"cache_read_tokens":9619856,"cache_write_tokens":0,"input_tokens":12568177,"output_tokens":248245,"reasoning_tokens":240647} ### Source [Original source](https://www.vals.ai/_astro/benchmark_view_ioi.CuUolFNv.json) Source Vals AI Original model label inception/mercury-2.5 Source version 2 Observed 2026-10-21T16:46:11.757Z Evidence SHA-256 `e1545b21b5b5c98d037aefa9d441b65859d07a10550f242d0e16162a49b8e8ab` Source locator `/tasks/ioi2026/inception~1mercury-2.5` | | | | | | | --- Cite as: IOI / ioi2026 — Benchize, https://benchize.com/benchmarks/vals-ai%3Aioi%3Aioi2026 (retrieved 2026-10-21)