Anthropic model field guide · checked July 29, 2026

Opus 5 is for hard work that must survive review.

Anthropic positions Claude Opus 5 between Sonnet 5 and Fable 5: a strong everyday model for coding and knowledge work, with effort controls, a faster paid mode, and explicit safety fallback behavior.

claude-opus-5 $5 input / $25 output per MTok Flowith: verify live

Access and price are surface-specific

Claude API

Model ID `claude-opus-5`; $5 input and $25 output per million tokens at launch.

Verify current aliases, snapshots, limits, and regional access.

Fast mode

Anthropic reports about 2.5× the default speed at twice the base API price.

Test end-to-end latency and accepted-task cost; speed is not a quality guarantee.

Claude plans

Available across Anthropic platforms; default on Max and positioned as the strongest model on Pro at launch.

Plan limits and selection behavior can change.

Flowith

No Flowith launch or entitlement is asserted on this page.

Use the live workspace model selector as the authority.

Selection protocol

Test the failure floor

Choose real tasks with acceptance tests: a difficult debugging case, a multi-document analysis, a tool workflow, and a long-horizon implementation. Run the same set on Opus 5 and Sonnet 5.

Record success rate, retries, tool calls, token use, latency, reviewer minutes, and defects found after acceptance. Use Fast mode only when latency changes the business outcome enough to justify the published premium.

Do not generalize provider benchmark results into a production guarantee. Your repository, permissions, tools, prompts, and review policy define the actual system.

Implementation paths

Official sources

  1. Introducing Claude Opus 5 — model role, price, availability, Fast mode, and fallback.
  2. Claude model overview — live identifiers, aliases, lifecycle, and properties.
  3. Refusals and fallback — current server-side behavior.

Claude Opus 5 FAQ

What is Claude Opus 5?

Claude Opus 5 is Anthropic's July 2026 Opus model for demanding everyday coding, knowledge work, analysis, and long-running agent tasks.

What is the Claude Opus 5 API model ID?

Anthropic's launch announcement names claude-opus-5. Check the current Claude Platform docs for snapshots, aliases, lifecycle, and regional availability.

How much does Claude Opus 5 cost?

Anthropic published base API pricing of $5 per million input tokens and $25 per million output tokens. Fast mode runs at twice the base price. Verify current pricing before deployment.

When should I choose Opus 5 instead of Sonnet 5?

Use a matched pilot. Opus 5 is the candidate for harder, longer-horizon work where fewer failures or less review can justify a higher rate. Sonnet 5 can be the better default when throughput and cost dominate.

Is Claude Opus 5 available in Flowith?

This guide does not claim Flowith availability. Verify the live Flowith workspace model selector.