IOI

    🏆 Leaderboard

    As of August 20, 2026, Claude Opus 5 is #1 for IOI at 91.7%. Ranked by the IOI score 45 models in this index have a published IOI score. IOI leaderboard with live API prices. IOI — International Olympiad in Informatics programming contest problems.

    Updated August 20, 2026282 models33 providers
    Claude Opus 5
    Anthropic · Proprietary
    91.7%$30.00
    GPT-5.6 Sol
    OpenAI · Proprietary
    86.7%$35.00
    Qwen3.8 MaxOSS
    Qwen · Open Source
    73%$8.00
    GPT-5.6 Luna
    OpenAI · Proprietary
    72.9%$1.40
    Claude Fable 5
    Anthropic · Proprietary
    72.3%$60.00
    GPT-5.4
    OpenAI · Proprietary
    67.8%$17.50
    GPT-5.6 Terra
    OpenAI · Proprietary
    65.3%$14.00
    GPT-5.2
    OpenAI · Proprietary
    54.8%$15.75
    Muse Spark 1.2
    Meta · Proprietary
    49.5%$5.50
    Claude Opus 4.7
    Anthropic · Proprietary
    47.1%$30.00
    Qwen3.7 Max
    Qwen · Proprietary
    46.8%$5.00
    GPT-5.3 Codex
    OpenAI · Proprietary
    43.8%$15.75
    Gemini 3 Flash
    Google · Proprietary
    39.1%$3.50
    Gemini 3 Pro
    Google · Proprietary
    38.8%$14.00
    DeepSeek-V4-Pro-0813OSS
    DeepSeek · Open Source
    35.8%$5.28
    Gemini 3.5 Flash-Lite
    Google · Proprietary
    26.2%$2.80
    Claude Opus 4.5
    Anthropic · Proprietary
    23.6%$30.00
    GPT-5.1
    OpenAI · Proprietary
    21.5%$11.25
    GPT-5.1 Codex
    OpenAI · Proprietary
    21.4%$11.25
    GPT-5
    OpenAI · Proprietary
    20%$11.25
    Gemini 2.5 Pro
    Google · Proprietary
    17.1%$11.25
    Qwen3 Max
    Qwen · Proprietary
    15.7%$5.50
    Grok 4.3
    xAI · Proprietary
    15.3%$3.75
    GPT-5.4 nano
    OpenAI · Proprietary
    15.3%$1.45
    Claude Opus 4.1
    Anthropic · Proprietary
    12.5%$90.00
    Grok-4 Fast Reasoning
    xAI · Proprietary
    11.5%$0.70
    GPT-5 Codex
    OpenAI · Proprietary
    9.8%$11.25
    Grok-4.1 Fast Non-Reasoning
    xAI · Proprietary
    7.7%$0.70
    GLM-4.7OSS
    Z AI · Open Source
    7.6%$2.80
    GPT-5 mini
    OpenAI · Proprietary
    6.8%$2.25
    MiniMax M2.5OSS
    MiniMax · Open Source
    6.7%$1.50
    Claude Sonnet 4
    Anthropic · Proprietary
    6.5%$18.00
    GPT-5.4 mini
    OpenAI · Proprietary
    6.4%$5.25
    MiniMax M2.7OSS
    MiniMax · Open Source
    4.9%$1.50
    o4-mini
    OpenAI · Proprietary
    4.8%$5.50
    Grok Code Fast 1
    xAI · Proprietary
    4.3%$1.70
    GLM-4.6OSS
    Z AI · Open Source
    4.3%$2.80
    Grok-4 Fast Non-Reasoning
    xAI · Proprietary
    3.8%$0.70
    Grok-4.1 Fast Reasoning
    xAI · Proprietary
    3.1%$0.70
    GLM-4.5OSS
    Z AI · Open Source
    2.9%$2.80
    Gemini 2.5 Flash
    Google · Proprietary
    2.6%$2.80
    MiniMax M2.1OSS
    MiniMax · Open Source
    2.3%$1.50
    DeepSeek-V3 0324OSS
    DeepSeek · Open Source
    1.7%$1.42
    Kimi K2 InstructOSS
    Moonshot AI · Open Source
    1.3%$1.00
    Qwen3 235B A22BOSS
    Qwen · Open Source
    0%$0.20
    ChatGPT-4o Latest
    OpenAI · Proprietary
    $12.50
    Claude 3 Haiku
    Anthropic · Proprietary
    $1.50
    Claude 3 Opus
    Anthropic · Proprietary
    $90.00
    Claude 3 Sonnet
    Anthropic · Proprietary
    $18.00
    Claude 3.5 Haiku
    Anthropic · Proprietary
    $4.80
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    The index

    All Large Language Models

    282 models across 33 providers. Search or jump to a lab — every model page stays linked here.

    Baidu

    1 models

    Inception

    1 models

    inclusionAI

    1 models

    LG AI Research

    1 models

    Nous Research

    1 models

    Sakana AI

    1 models

    StepFun

    1 models

    Tencent

    1 models

    Thinking Machines

    1 models

    Unisound

    1 models

    Upstage

    1 models

    Which model leads IOI right now?

    As of August 20, 2026, Claude Opus 5 by Anthropic is #1 for IOI at 91.7%. Ranked by the IOI score This board also tracks IOI. Next on the same board: GPT-5.6 Sol and Qwen3.8 Max. This ioi leaderboard ranks models by IOI. Scores come from public evals. Prices are the live API rates in the table above.

    Sources: OpenAI API pricing (https://developers.openai.com/api/docs/pricing); Anthropic Claude API pricing (https://platform.claude.com/docs/en/about-claude/pricing); Gemini API pricing (https://ai.google.dev/gemini-api/docs/pricing)

    Top 8 for ioi. Ranked by the IOI score Input and output are dollars per million tokens.
    RankModelIOIInput /MOutput /M
    1Claude Opus 591.7%$5.00$25.00
    2GPT-5.6 Sol86.7%$5.00$30.00
    3Qwen3.8 Max73%$2.00$6.00
    4GPT-5.6 Luna72.9%$0.20$1.20
    5Claude Fable 572.3%$10.00$50.00
    6GPT-5.467.8%$2.50$15.00
    7GPT-5.6 Terra65.3%$2.00$12.00
    8GPT-5.254.8%$1.75$14.00

    IOI FAQ

    Who ranks #1 on the IOI leaderboard?

    As of August 20, 2026, Claude Opus 5 by Anthropic ranks #1 on IOI at 91.7%. API pricing is $5.00/M input and $25.00/M output.

    What are the top models on IOI?

    The current IOI ranking as of August 20, 2026 is 1. Claude Opus 5 at 91.7%; 2. GPT-5.6 Sol at 86.7%; 3. Qwen3.8 Max at 73%.

    Which ioi model is the cheapest?

    Qwen3 235B A22B is the cheapest scored model on this ioi leaderboard at $0.10/M input and $0.10/M output ($0.20 blended). Claude Opus 5 still leads IOI at 91.7%.

    Should I always pick the #1 IOI model?

    Not automatically. Claude Opus 5 leads IOI, but a cheaper scored model can be the better production choice if the quality gap is small. Use the table to weigh IOI against input/output price, context window, and related evals.

    How often is the IOI leaderboard updated?

    Scores and API prices on this page are refreshed from published evals and provider rates. The snapshot is labeled August 20, 2026. Treat it as a current index, not a one-off blog post.

    What is IOI?

    IOI — International Olympiad in Informatics programming contest problems. This page ranks models that have published a IOI score, with live API token prices on the same row.

    Where is the IOI leaderboard?

    This page is the IOI leaderboard. Models are sorted by IOI, with input and output token prices on the same row so you can weigh score against cost. Official boards often omit price; that comparison is the point of this index.

    How is this IOI ranking different from the official board?

    Official eval pages own the methodology. This page keeps the published IOI score next to live API $/M so you can pick a production SKU, not only a trophy number.