whatmodel.sh / Claude Opus 4.1

Claude Opus 4.1 is a closed-weights language model from Anthropic, released August 2025. Licence: proprietary.

Catalogue identity notes

Comparison model from the Epoch AI internal-evaluation CSVs (Epoch release date 2025-08-05). Dated API snapshot claude-opus-4-1-20250805. Thinking budgets recorded per result. Anthropic model deprecations page: retired August 5, 2026.

67.1±0.8comparison only: no current run option verifiedfrom 20 benchmark results across 8 sources

$ how it compares

The LLMs ranked either side of Claude Opus 4.1, out of 828 with a score, then more from Anthropic.

#modelscorewhereRAMreleased
126Claude Opus 4 Anthropic67±1comparison only2025-05
127K-EXAONE 2.0 (750B-A37B) LG AI Research67±1local~791GB2026-07
128Claude Opus 4.1 Anthropic67±1comparison only2025-08
129Kimi K2 Thinking Moonshot AI67±1api $1.07/M +local~160GB2025-11
130Laguna M.1 Poolside67±2api price unknown +local~135GB2026-04
more from Anthropic
2Claude Opus 5.5 Anthropic87±1api $8.00/M2026-09
4Claude Fable 5.1 Anthropic85±1api $20.00/M2026-09
5Claude Sonnet 5.5 Anthropic84±1api $4.00/M2026-09

see all LLMs · find the ones that fit your machine

$ what it's good at

agent tasks▁▁▂▆█▆▅▄▄▃▂▁ #126 of 340 · 24% of its score · 5 tests

Beats o3-pro, o3, GPT-5 mini here, though they rank higher overall. Trails SmolLM3 3B, Jamba 1.5 Large, Nova 2 Pro (Preview) here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
SWE-bench Verified73.3% ✎▁··▁·▁▂▁▄█▄▁ beats 12/29hard · avg 19%▇▇▇▇▇ 14%sharp · at its level
τ-bench Retail lab82.4% ✎▁····▃·▂▇█▂▆ beats 28/28medium · avg 44%▇ 3.5%small run
τ²-bench Telecom lab71.5% ✎▁·▅█▆▅▂▃▃▂▃▁ beats 56/89hard · avg 29%▇ 3.1%sharp · noisy
τ-bench Airline lab56.0% ✎▁▁▁·▅▄▁█▇▁▃▇ beats 23/28hard · avg 26%▇ 2.4%at its level · small run
BFCL V4 (2025-11-03 archive, models absent from the December archive)71.2% ✎▃··▅▃▃·▅·▃·█ beats 9/10hard · avg 34%▇ 1.3%at its level
coding▁▁▁▃▅▇█▇▅▄▃▁ #100 of 524 · 26% of its score · 3 tests

Beats Grok 4.20 (0309 reasoning), Grok 4.3, Muse Glimmer 30B here, though they rank higher overall. Trails Llama 3.1 Nemotron Ultra 253B v1, Qwen3 235B-A22B Thinking 2507 here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
SWE-bench Verified73.3% ✎▁··▁·▁▂▁▄█▄▁ beats 12/29hard · avg 19%▇▇▇▇▇ 14%sharp · at its level
Arena WebDev (Code Arena)1389.4 ✎▁▂▄▃▅█▄▇▆▄▁▁ beats 40/119avg 981▇▇▇▇ 10%sharp
WebApp1K-Duo-React pass@1 (onekq-ai)76.9% ✎▁··▁·▁▁▁▆█▇█ beats 43/45hard · avg 32%▇ 2.5%at its level
chat & writing▁▁▁▃▅▄▆█▇▇▇▃ #61 of 463 * · 5.7% of its score · 1 test

Beats GPT-6 Luna, Grok 4.7, GPT-5.2 here, though they rank higher overall. Trails Gemma 4 31B here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
LMArena (text)1449.8 ✎▁▁▁▂▃▃▃▆▆▇█▃ beats 313/379avg 1268▇▇ 5.7%blunt
math▁▂▃▅▇▅▅█▄▁▁▁ #167 of 462 · 32% of its score · 3 tests

Beats MiMo-V2.5 (310B-A15B), MiniMax-M2.7 here, though they rank higher overall. Trails Qwen3-VL 4B Thinking, Granite 4.2 3B, DeepSeek R1 0528 Qwen3 8B here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
FrontierMath tiers 1–3 v212.6% ✎▂··▁▁▃▄▄█▅▃▃ beats 7/82very hard · avg 1.2%▇▇▇▇▇▇▇▇▇ 22%sharp · at its level
FrontierMath tier 4 v22.4% ✎▁▃▁▂█▅▂▂▁▁▁▁ beats 4/63very hard · avg 0.1%▇▇ 5.5%sharp · too hard for it
OTIS mock AIME 2024–202568.9% ✎▃▃▄▃▃▃▇▇█▃▂▅ beats 100/193very hard · avg 8.5%▇▇ 4.0%sharp · noisy
web search▂·▂▇▅█▃▄▁▂▁▁ #53 of 92 * · 2.3% of its score · 1 test

Beats Gemini 3.1 Pro (Preview), Qwen3.7 Max, GPT-5.2 here, though they rank higher overall. Trails GPT-4o mini (2024-07-18), Mistral Small 3.1 24B (2503), Llama 4 Scout (109B-A17B) here, though they rank lower overall.

testresultvs the others in its rundifficultycountswhy
Arena search systems (style controlled)1167.1 ✎▁·▁▁▂▃▂█▅▂▁▁ beats 8/30avg 1055▇ 2.3%blunt
other tests8 not in a task · 24% of its score
testresultvs the others in its rundifficultycountswhy
GPQA Diamond76.8% ✎▁▁▁▁▂▄▆▄▅▇█▅ beats 120/208hard · avg 40%▇▇▇ 8.5%sharp · at its level
KCL-Essay vanilla45.5% ✎▁···▁▃▂█▂▃▃▂ beats 18/23hard · avg 18%▇▇ 4.3%at its level
EBR-bench (Epoch)7.9% ✎▄▂·▆█▂▆▄▆▆·▄ beats 3/23very hard · avg 0.3%▇▇ 3.9%sharp · too hard for it
KCL-MCQA vanilla57.2% ✎▂···█▂▆▆██▆▂ beats 22/23very hard · avg 30%▇ 2.3%at its level
Mystery Game Puzzles (Epoch)21.0% ✎█··▂▃▇▄█▂▃▁▁ beats 36/74very hard · avg 9.4%▇ 2.3%sharp · too hard for it · noisy
Chess Puzzles (Epoch)7.0% ✎█▁▃▁▁▂▁▄▂▂▁▁ beats 50/135very hard · avg 5.9%▇ 2.3%sharp · noisy
Vectara hallucination leaderboard, 2025 dataset (HHEM-2.3, factual consistency rate)95.8% ✎▁▁▂▃▄▄█▆▃▂▂▁ beats 83/140very easy · avg 94%▇ 0.2%blunt · maxed out · noisy
Vectara hallucination leaderboard (HHEM-2.3, factual consistency rate)88.2% ✎▁▂▁▂▅█▂▃▄▃▁▁ beats 28/98very easy · avg 90%▇ 0.0%blunt

$ where to run it

No verified API or download recorded yet · add one

$ how the score was worked out · Epoch AI — internal evaluatio… 62%, LMArena leaderboard dataset 18%, Korean Canonical Legal Benchm… 7% and 5 more

Each result implies a score on its own, after adjusting for how hard its test is and who ran it. The 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's added up by who ran the tests. How it works

$ improve this page

Use a short GitHub form or edit the data through a pull request. Every number needs a source; here's which ones we can use.

data updated · sources and licences · json