Anthropic

Claude Opus 4

Claude Opus 4 is a proprietary model from Anthropic. It ranks #179 of 351 on the LMArena text leaderboard with a rating of 1377.

LMArena text1377+11 in 30 days
Rank#179/351
95% interval1373–1382
Votes35.9K
Developer
Anthropic
Released
Jun 1, 2025
Context window
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Price in / out, per 1M tokens
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Weights
Proprietary
Inputs
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Reasoning
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Tool use
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Claude Opus 4, LMArena text rating over time
13501360137013801390Jun 25Oct 25Feb 26Jun 26Oct 26
LatestClaude Opus 4 1377

The rating LMArena published at each update since Jun 1, 2025. Ratings move as votes come in and new models join.

Benchmarks

BenchmarkScore barAccuracyRankCost / test
LiveCodeBenchCoding62.63%104 / 143$15 / $75
MedQAMedicine92.87%26 / 92$15 / $75
GPQA DiamondReasoning71.72%92 / 138$15 / $75
MMLU-ProReasoning86.17%48 / 138$15 / $75
AIMEReasoning41.25%69 / 96$15 / $75
MMMUReasoning73.31%60 / 93$15 / $75

Vals AI, as of Oct 24, 2026.

LMArena, by category

LeaderboardRatingRankVotes
TextLMArena1377179 / 35135.9K
CodingLMArena1442115 / 3466.6K
MathLMArena1391176 / 3392.2K
Creative writingLMArena1386126 / 3494.5K
Instruction followingLMArena1406115 / 3519.2K
Hard promptsLMArena1399166 / 35116.2K
Multi-turnLMArena1396160 / 3496K
Long queriesLMArena1422108 / 3307K
ExpertLMArena1386172 / 3051.8K
Legal and governmentIndustries1373186 / 3252.9K
Medicine and healthcareIndustries1365197 / 3252.6K
Business and financeIndustries1344201 / 3446K
ChineseLanguages1387190 / 3282.4K
SpanishLanguages1389158 / 249861
GermanLanguages1391131 / 261957
FrenchLanguages1371175 / 252522
JapaneseLanguages1330144 / 236834
VisionLMArena119299 / 1461.3K

LMArena, CC BY 4.0, as of Oct 22, 2026. Where a model is rated at several effort levels, its best is shown (Claude Opus 4 (Thinking 16K, 20250514), Claude Opus 4 (20250514)).

Compare Claude Opus 4

Anthropic

An AI safety and research company that builds the Claude family of models, known for coding, long context and careful behaviour. Founded 2021, based in San Francisco. anthropic.com

Questions

Who makes Claude Opus 4?

Claude Opus 4 is made by Anthropic, founded 2021 and based in San Francisco.

How does Claude Opus 4 rank?

#179 of 351 on LMArena’s text leaderboard, rated 1377 (95% interval 1373–1382) from 35,908 votes, as of Oct 22, 2026.

Is Claude Opus 4 open source?

No. Claude Opus 4 is proprietary and served through its provider’s API.

Sources

Every number on this page comes from these sources; models without a published number show none. Download the data. Cite as “Nexus Explorer, nexus.inc/models”.