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Anthropic

Claude Opus

#1of 28 · general

Opus 5.5

1Mcontext
$4 / $20per 1M in / out
2026-09-22released
2026-06-01knowledge cutoff
50100Coding 91 · #2 of 28Agents 90 · #1 of 29Cyber 29 · #12 of 24Engineering 96 · #1 of 26Math 85 · #2 of 26Health 87 · #2 of 24Legal 75 · #4 of 27Professional 91 · #1 of 28Writing 78 · #2 of 21Instruct 64 · #7 of 25Hallucination 68 · #3 of 26Multimodal 83 · #1 of 24
Coding91#2
Agents90#1
Cyber29#12
Engineering96#1
Math85#2
Health87#2
Legal75#4
Professional91#1
Writing78#2
Instruct64#7
Hallucination68#3
Multimodal83#1

History

LiveBench score70.072.575.077.580.082.585.0Jan 2026Apr 2026Jul 2026Oct 2026Claude Opus 4.5 · $5/M in · 2025-11-24 · still served · LiveBench 72.6 LiveBench score (0–100)Claude Opus 4.6 · $5/M in · 2026-02-05 · still served · LiveBench 74.5 LiveBench score (0–100)Claude Opus 4.7 · $5/M in · 2026-04-16 · still served · LiveBench 76.5 LiveBench score (0–100)Claude Opus 4.8 · $5/M in · 2026-05-28 · still served · LiveBench 76.2 LiveBench score (0–100)Claude Opus 5 · $5/M in · 2026-07-24 · still served · LiveBench 80.1 LiveBench score (0–100)Claude Opus 5.5 · $4/M in · 2026-09-22 · still served · LiveBench 83.2 LiveBench score (0–100)54.84.74.64.5
  • Anthropic
  • older → newer
$ / M input tokens6 of 176 priced models · price is a third-party claim, not a vendor quote

Effort

Opus 5.5
% of best score7080901000.2×0.5×1×2×× the best effort’s cost · log scaleLowMedHighXhighMax

Measured

≈ imputed · amber dot = lab-self-reported among the sources
GPQA Diamond90.6%#15Epoch AI
HLE61.4%#1Artificial Analysis
LiveBench83.2%#2LiveBench
SciCode66.9%#1Artificial AnalysisEpoch AI
CritPt31.7%#1Artificial AnalysisEpoch AI
Terminal-Bench87.6%#1Vals.ai
APEX Agents73.5%#3Epoch AI
GDPval68.3%#1Artificial Analysis
Arena1507#2Arena
AA Index57.6#1Artificial Analysis
Vals Index67.0#2Vals.ai
Epoch Capabilities Index168.8#1Epoch AI

Neighbors

Claude Fable→ less factual · pricierGPT Astra→ weaker professional · pricierGemini Argon→ follows instructions better · cheaperKimi→ weaker multimodal · cheaperClaude Sonnet→ weaker professional · cheaper