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Claude Opus 4.8 vs Claude Sonnet 4.5

Head to head on 25 shared benchmarks, with price, context window, and release dates.

Benchmark scores

99

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Model
Claude Opus 4.8

Anthropic

66.7%1835elo80.847.2%92.0%48.7%62.2%80.1%79.3%78.3%67.4%81.4%84.3%89.7%53.2%85.8%69.9%83.4%69.0%54.8%53.5%75.6%58.3%82.7%94.4%-------15.5%-80.4%14.5%---67.0%--1281elo40.0%--53.9%13.4%-22.5%1890elo-----56.9%----10.4%------91.8%-------------------69.2%----82.7%-60.9%70.9%--63.4%
Claude Sonnet 4.5

Anthropic

60.8%1675elo71.415.2%72.7%7.2%42.7%70.7%80.4%57.0%53.4%76.5%79.3%77.6%40.6%84.5%64.0%62.9%19.0%32.9%42.8%73.3%28.8%22.6%70.5%0.0%0.0%37.0%1000.0%0.0%0.0%-5.0%--0.0%0.0%0.0%-0.0%0.0%--0.0%0.0%--0.0%--0.0%83.9%0.0%0.0%0.0%-0.0%0.0%87.5%83.8%-0.0%0.0%59.0%0.750.750.0%-0086.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%0.0%00.0%0.0%77.2%67.0%74.8%-0.0%0050.34-0--0.0%1.4927.5%
2 / 2 models
AttributeClaude Opus 4.8

Anthropic

Claude Sonnet 4.5

Anthropic

DescriptionClaude Opus 4.8 (Adaptive Reasoning, Max Effort) is an AI model from Anthropic.anthropic/claude-sonnet-4.5 is an AI model.
FamilyClaudeClaude
Params-Undisclosed (closed)
Open weights-closed
License-Proprietary
Released28 May 202629 Sep 2025
Context1,000,0001,000,000
Input $/1M$5.00$3.00
Output $/1M$25.00$15.00
Cache read $/1M$0.500$0.300
Cache write $/1M$6.250$3.750
Speed0 tok/s0 tok/s
Latency0.00 s0.00 s
Modalitiestext, image, filetext, image, file
Providers-anthropic, aws-bedrock, vertex-ai
PublisherAnthropicAnthropic
Reported scores
LiveBench - Math79.3% (LiveBench)
LiveBench - Coding80.4% (LiveBench)
LiveBench - Language76.5% (LiveBench)
LiveBench - Data Analysis57.0% (LiveBench)

FAQ

Is Claude Opus 4.8 or Claude Sonnet 4.5 better?
Across the 25 benchmarks both models report on Sophon, Claude Opus 4.8 leads on 24 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
How do Claude Opus 4.8 and Claude Sonnet 4.5 compare on GPQA Diamond?
Claude Opus 4.8 scores 92.0% and Claude Sonnet 4.5 scores 72.7% on GPQA Diamond.
Which is cheaper, Claude Opus 4.8 or Claude Sonnet 4.5?
Claude Sonnet 4.5 is cheaper at $15.00 per million output tokens against $25.00 for Claude Opus 4.8 - about 1.7x.
When were Claude Opus 4.8 and Claude Sonnet 4.5 released?
Claude Opus 4.8 was released 28 May 2026 by Anthropic. Claude Sonnet 4.5 was released 29 Sep 2025 by Anthropic.

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