[whatmodel.sh](../../README.md) / Claude Opus 4.8 # Claude Opus 4.8 Anthropic · released 2026-05 · closed weights **score 76.4** ±0.4 · #24 of 732 · from 62 benchmark results across 17 sources Score within the [LMArena (text)](https://whatmodel.sh/?set=lmarena-text&score=set) comparison set only. ## What it's good at ● marks Claude Opus 4.8 among every model on that task or test, worst to best.
task                vs the others         rank  counts  tests
agent tasks         ▁▁▃▆█▄▅▅▄▄●▁    #17 of 313     29%     19
coding              ▁▁▁▃▅▇█▇▅▄●▁    #39 of 469     15%      7
chat & writing      ▁▁▁▃▆▄▆█▆▇▇●   #23 of 402*    2.1%      2
math                ▁▁▃▅█▆▄█▄●▁▁    #19 of 431     35%     16
vision & documents  ▁▁▂▂▁▃▄▂▆▇●▄    #16 of 153    3.5%      4
web search          ▁▁▁▅▄●▃▄·▁·▁     #29 of 84    3.9%      5
agent tasks · #17 of 313 · 29% of its score Beats [Muse Wonder](muse-wonder.md), [GPT-5.5](gpt-5-5.md), [MiMo-V2.6-Pro](mimo-v2-6-pro.md) here, though they rank higher overall.
test                                    result  vs the others in its run    difficulty            counts  why
Arena Agent (October 2026 aggrega…  0.0664 IPS  ▁▁▁▃▃▂█●▂▂▁▁ beats 47/59    avg -0.379 IPS          4.8%  sharp
SWE-bench Pro (split unspecified)…       69.2%  ▄█·●·▄██···▄ beats 3/9      very hard · avg 7.4%    4.5%  sharp · at its level
SWE-bench Multilingual (maker)           84.4%  ▃··▃·●▃▃█··▃ beats 3/9      hard · avg 31%          2.1%  typical
Terminal-Bench 4.0                       23.6%  █▅▅▅●·▅▃▃▅▅▅ beats 9/20     very hard · avg 0.5%    2.0%  sharp · at its level
SWE-bench Verified (maker)               88.6%  ▁▁▁▁▁▁▂▄█▆●▁ beats 135/138  hard · avg 28%          1.9%  sharp
τ³-bench banking_knowledge (v1.0.…       39.7%  ▃▃▂▃·▆▃▂●▅▅▂ beats 17/25    very hard · avg 4.3%    1.4%  at its level
Chartography with tools (maker)          75.0%  ▃········●██ beats 1/7      very hard · avg 6.5%    1.3%  sharp · at its level
Terminal-Bench 2.1 (maker)               82.7%  ▁·▁·▁▁▄▃▆█●█ beats 46/63    hard · avg 19%          1.3%  sharp
OSWorld-Verified (maker)                 83.4%  █▃·▂▅▂▃▂▅▃▆● beats 24/27    hard · avg 28%          1.2%  typical
Humanity's Last Exam with tools (…       57.9%  ▁······▁·●·█ beats 4/10     very hard · avg 14%     1.2%  at its level
E2E-SWE (build a working codebase…       51.9%  ▃··▅··▃█▃●▃▅ beats 9/12     very hard · avg 3.7%    1.2%  sharp · at its level
Toolathlon (Tool Decathlon) (make…       59.9%  █···█··█·█●█ beats 4/5      hard · avg 16%          1.0%  at its level
DeepSWE v1.1 (resolved) (maker)          59.0%  ●·····████·█ beats 0/5      hard · avg 19%          1.0%  at its level
MCP-Atlas (public set)                   77.8%  █··█·██·███● beats 7/7      hard · avg 30%          0.9%  typical
BrowseComp with context managemen…       84.3%  ▄·▄▂·█▂·●▄·▂ beats 11/15    medium · avg 47%        0.8%  typical
Legal Research Bench (agentic, al…       42.9%  ▄█··▄▄▄██·▄● beats 12/12    very hard · avg 6.3%    0.6%  at its level
KlinikeBench strict pass@1 (333 i…       16.8%  ▁▁·▁▁▁▁▅▃●▅█ beats 17/27    very hard · avg 2.4%    0.6%  typical
RWSearch                                 77.3%  █●██··█····█ beats 1/5      medium · avg 45%        0.6%  typical
Toolathlon-Verified (maker)              79.9%  ▃·····█···●▃ beats 4/5      medium · avg 37%        0.5%  blunt · at its level
coding · #39 of 469 · 15% of its score Beats [GPT-5.5](gpt-5-5.md), [GPT-5.6 Terra](gpt-5-6-terra.md) here, though they rank higher overall. Trails [Qwen3.8 27B](qwen3-8-27b.md), [GLM-5.2](glm-5-2.md), [GLM-5.3-Flash](glm-5-3-flash.md) here, though they rank lower overall.
test                                result  vs the others in its run    difficulty            counts  why
SWE-bench Pro (split unspecified)…   69.2%  ▄█·●·▄██···▄ beats 3/9      very hard · avg 7.4%    4.5%  sharp · at its level
Arena WebDev (Code Arena)           1555.8  ▁▁▃▂▅█▃●▅▅▁▂ beats 89/129   avg 981                 3.3%  sharp
SWE-bench Multilingual (maker)       84.4%  ▃··▃·●▃▃█··▃ beats 3/9      hard · avg 31%          2.1%  typical
SWE-bench Verified (maker)           88.6%  ▁▁▁▁▁▁▂▄█▆●▁ beats 135/138  hard · avg 28%          1.9%  sharp
E2E-SWE (build a working codebase…   51.9%  ▃··▅··▃█▃●▃▅ beats 9/12     very hard · avg 3.7%    1.2%  sharp · at its level
Luau Leetcode fully solved (Torpe…   79.8%  ▁▁▁▁·▁▂▃▅▃●▇ beats 33/49    hard · avg 17%          1.1%  sharp
DeepSWE v1.1 (resolved) (maker)      59.0%  ●·····████·█ beats 0/5      hard · avg 19%          1.0%  at its level
chat & writing · #23 of 402 · 2.1% of its score Beats [GPT-6 Astra](gpt-6-astra.md), [Claude Sonnet 5.5](claude-sonnet-5-5.md), [GPT-6 Sol](gpt-6-sol.md) here, though they rank higher overall. Trails [Gemini 3.6 Flash](gemini-3-6-flash.md), [Muse Spark 1.2](muse-spark-1-2.md), [Muse Spark 1.1](muse-spark-1-1.md) here, though they rank lower overall.
test                              result  vs the others in its run    difficulty      counts  why
LMArena (text)                    1481.7  ▁▁▁▂▃▃▃▆▆▇█● beats 364/385  avg 1260          1.9%  blunt
IFEval (aggregation unspecified)   86.0%  ●·██·█···█·█ beats 0/5      easy · avg 72%    0.2%  maxed out
math · #19 of 431 · 35% of its score Beats [DeepSeek V4.1 Flash 1017](deepseek-v4-1-flash-1017.md), [Qwen3.8 Max (2.4T-A95B)](qwen3-8-2-4t-a95b.md) here, though they rank higher overall. Trails [GPT-5.6 Luna](gpt-5-6-luna.md), [GPT-6 Luna](gpt-6-luna.md) here, though they rank lower overall.
test                                result  vs the others in its run    difficulty            counts  why
FrontierMath tier 4 v2               56.1%  ▁▂▁▂█▅●▃▂▁▁▁ beats 51/67    very hard · avg 0.1%    8.4%  sharp · at its level
FrontierMath tiers 1–3 v2            80.0%  ▂··▁▁▃▄▄█▆●▃ beats 70/86    very hard · avg 1.2%    6.8%  sharp
MathArena ArXivMath April 2026 (4…   62.5%  ▁·····▅█●▄·▁ beats 14/20    very hard · avg 7.6%    3.6%  sharp · at its level
MathArena ArXivMath June 2026 (48…   70.0%  ▂···▄·██●▆▄▂ beats 11/19    very hard · avg 5.1%    3.6%  sharp · at its level
MathArena ArXivMath February 2026…   60.2%  ▁▁▁▁█▇▄▃▁●·▃ beats 21/24    very hard · avg 9.4%    2.2%  at its level
MathArena ArXivMath March 2026 (3…   75.0%  █▃▅·█▃▃·▅·●▃ beats 13/14    hard · avg 16%          1.6%  at its level
MathArena BrokenArXiv April 2026 …   34.4%  ▂▂▆█●▃▂▂▂··▂ beats 12/18    very hard · avg 0.8%    1.5%  sharp · at its level · noisy
MathArena ArXivMath May 2026 (40 …   65.0%  ▁··▁▄█●▁·▃·▁ beats 12/17    very hard · avg 11%     1.2%  at its level
MathArena ArXivLean June 2026 (46…   23.9%  ▄····▄▄█●█·▄ beats 6/9      very hard · avg 0.9%    1.2%  sharp
MathArena BrokenArXiv June 2026 (…   41.7%  ▄··█▂▂●▆▄··▂ beats 8/14     very hard · avg 1.3%    1.0%  sharp · at its level · noisy
MathArena BrokenArXiv May 2026 (5…   23.0%  ██·▄▄●····▄▄ beats 6/8      very hard · avg 1.9%    1.0%  sharp · at its level
MathArena BrokenArXiv March 2026 …   35.7%  █·▆█▂·●▂···▂ beats 12/14    very hard · avg 1.0%    0.9%  sharp · at its level · noisy
MathArena BrokenArXiv February 20…   35.5%  ▃▂▂▃█▃▂·●··▂ beats 14/16    very hard · avg 0.9%    0.9%  sharp · at its level · noisy
IMO-AnswerBench                      75.3%  ▁▁·▁▁▁▄●█▄▂▃ beats 16/44    hard · avg 25%          0.6%  typical
USAMO 2026 (maker)                   96.7%  █·██······●█ beats 3/4      hard · avg 19%          0.4%  sharp · noisy
OTIS mock AIME 2024–2025             98.3%  ▃▃▄▃▃▃▇▇█▃●▅ beats 175/197  very hard · avg 7.2%    0.2%  sharp · maxed out · noisy
vision & documents · #16 of 153 · 3.5% of its score Beats [Claude Sonnet 5.5](claude-sonnet-5-5.md), [GPT-6 Sol](gpt-6-sol.md), [GPT-5.5](gpt-5-5.md) here, though they rank higher overall. Trails [Muse Spark 1.2](muse-spark-1-2.md), [Qwen3.8-Flash-Next](qwen3-8-flash-next.md), [Qwen3.8-Omni-Flash](qwen3-8-omni-flash.md) here, though they rank lower overall.
test                                result  vs the others in its run    difficulty      counts  why
Arena vision (style controlled)     1285.7  ▁▁▂▂▂▂▃▄▅▅█● beats 137/152  avg 1061          1.2%  blunt
CharXiv (reasoning questions) (ma…   80.5%  ███··█·●█··█ beats 4/6      hard · avg 28%    1.1%  typical
Arena document (style controlled)   1485.9  ▁▁▃▃▄▃▇█▅▇●▅ beats 31/37    avg 1331          0.6%  blunt
SciDocBench scientific-document w…   53.4%  ▃▃···█▃●▃·▃▅ beats 6/11     hard · avg 25%    0.6%  blunt · at its level
web search · #29 of 84 · 3.9% of its score Trails [GPT-4o mini (2024-07-18)](gpt-4o-mini-2024-07-18.md), [Mistral Small 3.1 24B (2503)](mistral-small-3-1.md), [GPT-4o (2024-08-06)](gpt-4o-2024-08-06.md) here, though they rank lower overall.
test                                result  vs the others in its run  difficulty            counts  why
Humanity's Last Exam with tools (…   57.9%  ▁······▁·●·█ beats 4/10   very hard · avg 14%     1.2%  at its level
BrowseComp with context managemen…   84.3%  ▄·▄▂·█▂·●▄·▂ beats 11/15  medium · avg 47%        0.8%  typical
Arena search systems (style contr…  1195.2  ▁·▁▁▂▂▂●▆▃▂▂ beats 18/36  avg 1069                0.7%  blunt
Legal Research Bench (agentic, al…   42.9%  ▄█··▄▄▄██·▄● beats 12/12  very hard · avg 6.3%    0.6%  at its level
RWSearch                             77.3%  █●██··█····█ beats 1/5    medium · avg 45%        0.6%  typical
other tests (17)
test                                result  vs the others in its run    difficulty            counts  why
EBR-bench (Epoch)                    28.6%  ▄▂·▆█▂●▆▄▆·▆ beats 13/25    very hard · avg 0.3%    4.0%  sharp · at its level
Mystery Game Puzzles (Epoch)         36.0%  █··▂▃▇▄●▂▄▂▁ beats 58/77    very hard · avg 9.4%    3.5%  sharp · at its level · noisy
Furniture Assembly (Epoch)           42.5%  █▆▆▆●▂▆▂▂▂▂▅ beats 18/32    very hard · avg 1.2%    3.3%  sharp · at its level
GPQA Diamond                         91.0%  ▁▁▁▁▂▄▆▄▅▇●▅ beats 184/211  hard · avg 39%          2.2%  sharp · small run · several runs
Humanity's Last Exam (maker)         49.8%  ▂·····▂·▄●█▄ beats 4/10     very hard · avg 5.9%    2.2%  at its level
ARC-AGI-2 public evaluation set (…   76.9%  █··▂▅▁▃▁▃·▁● beats 23/24    very hard · avg 0.3%    2.1%  sharp · at its level · noisy
Chess Puzzles (Epoch)                34.0%  █▁▁▁▁▂▃▃●▂▁▁ beats 111/137  very hard · avg 5.8%    1.9%  sharp · at its level · noisy
Legal Research Bench (single-shot…    8.7%  ▃▃█▃·▅···█▃● beats 12/12    very hard · avg 0.8%    0.9%  too hard for it
AgentWorldBench (open-ended, over…   56.6%  ▄▄··▄▄·▄█▄●█ beats 9/11     hard · avg 26%          0.9%  blunt · at its level
SimpleQA Verified                    53.0%  ▁▁▃▂▃▃▆▆●▄▂▅ beats 60/81    very hard · avg 8.0%    0.7%  at its level
Icelandic LLM Leaderboard average…   63.9%  ▁▁▃▂▂▄▁▃▄▄●█ beats 29/38    very hard · avg 14%     0.7%  at its level
FORTE (AGI-Eval)                     77.2%  ▄···█·····●█ beats 3/5      medium · avg 38%        0.6%  typical
WritingBench                         85.2%  ▁·▁▂▁··▅●▂▂▁ beats 13/20    medium · avg 54%        0.6%  typical
ARC-AGI-1 public evaluation set (…   95.5%  ▁·▇▃▁·█▇▁·●▃ beats 24/27    very hard · avg 4.0%    0.5%  sharp · noisy
HealthBench (maker)                  58.8%  ●·▄·····▄▄▄▄ beats 0/6      hard · avg 30%          0.5%  blunt · at its level
RobloxQA v2.0 multiple choice (To…   96.7%  ▁▁▃▁█▄▃▃●▂▂▂ beats 38/49    easy · avg 77%          0.4%  maxed out
NTCIR SciClaimEval Subtask 1 pair…   67.6%  ▃▃···▃·▃●█·▃ beats 4/8      medium · avg 45%        0.3%  blunt · at its level
## How the score was worked out Each result implies a score on its own, after adjusting for how hard that test is and who ran it. The model's score is their weighted average, with a small pull toward the middle for thinly tested models. Each test's weight is its *counts* column above; here it is added up by who ran the tests. [Method](../method.md)
source                                    results  share of the score
Epoch AI                                        9   30% ▇▇▇▇
Anthropic system cards and model announ…       15   21% ▇▇▇
MathArena ArXivMath / BrokenArXiv / ArX…       11   19% ▇▇
LMArena leaderboard dataset                     6   12% ▇
meituan-longcat/LongCat-2.0 model card          6    4% ▇
ARC Prize Foundation model_baseline out…        2    3% ▇
Terminal-Bench 4.0 official leaderboard…        1    2% ▇
Legal Research Bench                            2    2% ▇
Roblox LLM Leaderboard                          2    2% ▇
τ²/τ³-bench leaderboard: Sierra's own e…        1    1% ▇
E2E-SWE: Benchmarking LLMs on Building …        1    1% ▇
Qwen/Qwen-AgentWorld-35B-A3B model card         1    1% ▇
zai-org/GLM-5.2 model card                      1    1% ▇
Miðeind Icelandic LLM Leaderboard               1    1% ▇
SciDocBench: A Workflow-Centered Benchm…        1    1% ▇
KlinikeBench: Evaluating Language Model…        1    1% ▇
SciTrue: Reliable Scientific Claim Vali…        1    0% ▇
prior: pull toward the middle                        0% ▇
weighted average                                   = 76.4
Licences: Epoch AI ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · MathArena ArXivMath / BrokenArXiv / ArXivLean model-output datasets ([CC BY-SA 4.0](../../licenses/matharena-sharealike-NOTICE.txt)) · LMArena leaderboard dataset ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · meituan-longcat/LongCat-2.0 model card ([mit](../../licenses/meituan-longcat--LongCat-2.0.txt)) · ARC Prize Foundation model\_baseline outputs on ARC-AGI-1/2 public evaluation sets ([MIT](../../licenses/arcprize-model-baseline-outputs-MIT.txt)) · Terminal-Bench 4.0 official leaderboard submissions ([Apache-2.0](../../licenses/terminal-bench-leaderboard-submissions-Apache-2.0.txt)) · Legal Research Bench ([CC-BY-4.0](https://creativecommons.org/licenses/by/4.0/)) · Roblox LLM Leaderboard ([MIT](../../licenses/roblox-llm-leaderboard-MIT.txt)) · τ²/τ³-bench leaderboard: Sierra's own evaluation runs ([MIT](https://opensource.org/license/mit)) · E2E-SWE: Benchmarking LLMs on Building Working Codebases from Scratch ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · Qwen/Qwen-AgentWorld-35B-A3B model card ([Apache-2.0](https://huggingface.co/Qwen/Qwen-AgentWorld-35B-A3B/blob/60d2b0434a53d2e62a7c00a489586815d94ebffb/README.md)) · zai-org/GLM-5.2 model card ([mit](../../licenses/zai-org--GLM-5.2.txt)) · Miðeind Icelandic LLM Leaderboard ([CC BY 4.0](../../licenses/mideind-icelandic-llm-leaderboard-CC-BY-4.0.txt)) · SciDocBench: A Workflow-Centered Benchmark and Data Pipeline for Scientific Document Understanding ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · KlinikeBench: Evaluating Language Models Beyond Diagnostic Accuracy ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · SciTrue: Reliable Scientific Claim Validation with Frontier and Open Language Models at the NTCIR SciClaimEval Task ([CC BY 4.0](../../licenses/paper-2609.00654v1-CC-BY-4.0.txt)) ## How to run it ### Through an API api (Anthropic) · $10.00/M blended · $5 in / $25 out per 1M tokens · [docs.anthropic.com](https://docs.anthropic.com/en/docs/about-claude/models) [price source](https://github.com/anomalyco/models.dev/blob/a668908cfe7073faa0363699486fc41a3ff52412/providers/anthropic/models/claude-opus-4-8.toml): Standard base token rate from models.dev. Provider-specific tiers, long-context surcharges, caching and promotions may differ. · [context source](https://github.com/anomalyco/models.dev/blob/a668908cfe7073faa0363699486fc41a3ff52412/models/anthropic/claude-opus-4-8.toml) [interactive version](https://whatmodel.sh/model/claude-opus-4-8) · [JSON](https://whatmodel.sh/api?format=json&all=1)