Claude Opus 5

Anthropic · July 2026

Strong at complex code and work that runs over many steps.

Superseded by Claude Opus 5.5 →

  • Modalities

  • Context window

    1,000,000 tokens, ≈ 750,000 words · about 3,000 pages

  • Max output

    128,000 tokens, ≈ 96,000 words in a single answer

  • Knowledge cutoff

    May 2026

Reasoning effort

Default: High

  • Low

  • Medium

  • High

  • X-High

  • Max

Providers

Files you can attach

  • ImagesJPG, PNG, GIF, WEBP
  • DocumentsPDF
  • Text and codeTXT, MD, CSV, TSV, RPT, LOG, PY, TS, TSX, JS, JSX, CS, GO, JAVA, KT, SWIFT, CPP, C, H, PHP, RB, SQL, SH, PS1, HTML, CSS, SCSS, JSON, YAML, YML, XML, INI

Tools

  • Web searchSupported
  • Code interpreterSupported

Features

  • StreamingSupported
  • Function callingSupported
  • Structured outputsSupported
  • Fine-tuningNot supported

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