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Claude Opus 4.6

Model facts

Provider: Anthropic
Released: 2026-02-05
Retirement: 2027-02-05

Technical details

Model ID: claude-opus-4-6
Status: Active
Context window: 1,000,000 tokens
Max output: 128,000 tokens
Knowledge cutoff: 2025-05-31
Input modalities: Text, Image, PDF
Output modalities: Text
Pricing (per 1M tokens): $5 in / $25 out
Tool use: Yes

Links

models.dev entry

Claude Opus chronology

Preceded by

Claude Opus 4.5

Succeeded by

Claude Opus 4.7

Claude chronology

Preceded by

Claude Opus 4.5

Succeeded by

Claude Sonnet 4.6

A large language model by Anthropic.

Details

First Claude model where prefill was disabled on the developer API.

Anthropic — Eval awareness in Claude Opus 4.6’s BrowseComp performance
LessWrong post gathering initial Twitter reactions