Cyberax AI Playbook
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Model · Anthropic · Text

Claude Opus 4.8

The Opus-tier flagship of the Claude 4 generation, for complex reasoning and long-horizon agentic coding. Superseded by Claude Opus 5 (2026-07-24) but still available on every platform.

Modality
Text
License
Proprietary (Proprietary)
Context window
1,000,000 tokens 1M default; 200k on Microsoft Foundry. Uses a new tokenizer.
Released
May 28, 2026
Last verified
September 8, 2026
Runs locally
No
Also handles
vision

Strengths

  • Strongest Opus-tier model for nuanced reasoning and long-horizon agentic coding
  • 1M-token context with up to 128k output (300k via Batch API beta)
  • Adaptive thinking with effort defaulting to high

Weaknesses

  • Premium pricing ($5/$25 per MTok; fast mode $10/$50); slower than Sonnet and Haiku tiers
  • Closed weights — cannot be self-hosted

Try it

WhereTypeNotes
Anthropic API hosted-api API key required
AWS Bedrock hosted-api Enterprise / regional
Google Vertex AI hosted-api GCP integration
Claude.ai product Paid plans (Pro and above)

Version history

  1. Claude Opus 4.8 May 2026 Current Deprecated
  2. Claude 4.6 Sonnet Feb 2026 Deprecated
  3. Claude 4.7 Opus Feb 2026 Deprecated
  4. Claude Haiku 4.5 Oct 2025

Change log

  • — Deprecated — superseded by Claude Opus 5 (released 2026-07-24). Opus 4.8 moves to Anthropic's legacy table; still available on all platforms, retirement not sooner than 2027-05-28.
  • — Repositioned as Anthropic's most capable Opus-tier model: Claude Fable 5 launched 2026-06-09 as a new tier above Opus. Opus 4.8 is not superseded and remains the standard-lineup flagship.
  • — Initial entry (2026-06-08 catalog refresh, Tier 3). Current flagship Opus, released 2026-05-28; supersedes Claude 4.7 Opus.