WeavePrism

Claude Sonnet 4.5 vs GPT-5.1

GPT-5.1 costs 43% less at typical usage ($3.44 vs $6.00 per 1M tokens). They're tied on task-quality scores, 5 tasks each.

SpecClaude Sonnet 4.5GPT-5.1
Input /1M$3.00$1.25
Output /1M$15.0$10.0
Typical /1M$6.00$3.44
Context window200k400k
SpeedBriskBrisk
PrivacyStrongStandard
Open weightsNoNo
Claude Sonnet 4.5
Steady since we started tracking (Jul 13, 2026)
Steady since we started tracking (Jul 13, 2026)
GPT-5.1
Steady since we started tracking (Jul 13, 2026)
Steady since we started tracking (Jul 13, 2026)

Quality by task

Coding95/94
Agents95/93
Reasoning93/96
Writing93/92
Chat91/93
Classify88/88
Extract90/89
Summarize92/91
Translate88/90
Vision90/94
General93/94

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Also compare Claude Sonnet 4.5

Prices are list $/1M tokens, hand-maintained from public provider pricing. Task scores are benchmark-informed 0-100 estimates, not gospel — validate on your own evals before moving production traffic. Not affiliated with any model provider.