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Decision summary

  • New Opus route -> Claude Opus 5.5
  • Client requires computer_20251124 on Claude API or Google Cloud -> stay on Opus 5 until you migrate
  • Cache-heavy agents -> Opus 5.5 at $0.20 cache reads
  • Need a replay before cutover -> run the same tasks on both IDs
  • Lower than Opus prices -> Claude Sonnet 5, not Opus 5

Claude Opus successor comparison

Frontier comparison

Claude Opus 5.5 vs Claude Opus 5

Claude Opus 5.5 replaces Claude Opus 5 as the latest Opus-tier model.

Featured · Updated today · Last verified: September 2026

Choose Claude Opus 5.5 when

Current Opus-tier agents, coding migrations, and knowledge work.

Choose Claude Opus 5 when

Pinned Opus 5 clients until they absorb the Opus 5.5 breaking changes.

  • New Opus route: Claude Opus 5.5
  • Client requires computer_20251124 on Claude API or Google Cloud: stay on Opus 5 until you migrate
  • Cache-heavy agents: Opus 5.5 at $0.20 cache reads

Decision axes: Best for · Access and platforms · Context window · Input and output

Reasoning

Opus 5.5 thinking cannot be disabled. That is a breaking change from Opus 5.

Coding

Anthropic reports higher coding scores and a lower typical bill at default settings.

Multimodal

Text and image in, text out.

Speed

Anthropic says output is more than 30% faster. Treat that as their test, then measure yours.

Enterprise

Same Claude platforms, with computer_20251124 rejected on the Claude API and Google Cloud.

Curated matrix for Claude Opus 5.5 vs Claude Opus 5 — confirm live limits and pricing on each vendor’s official pages.

How they compare

Criterion-by-criterion notes from the catalog—not a ranking. Validate on your own gold set.

CriterionClaude Opus 5.5Claude Opus 5
Best forCurrent Opus-tier agents, coding migrations, and knowledge work.Pinned Opus 5 clients until they absorb the Opus 5.5 breaking changes.
Access and platformsclaude-opus-5-5, released September 22, 2026, on Claude API and major clouds.claude-opus-5 remains callable; this catalog marks it superseded by Opus 5.5.
Context window1M context; 128K synchronous output; up to 300K on the Message Batches API with the output-300k beta header.1M-class Opus context as previously documented. Confirm the live card before a new build.
Input and outputText and image in; text out.Text and image in; text out.
Reasoning controlAdaptive thinking always on. Default effort medium. Effort steers depth.Adaptive thinking. Opus 5.5 changes which controls can turn thinking off.
Coding and agentsAnthropic reports large gains versus Opus 5 on long coding jobs and says a 680,000-line migration finished in under a day in one early test.Prior Opus agent default. Anthropic's new table shows lower coding and computer-use scores than Opus 5.5.
Cost posture$4 / $20. Cache read $0.20 (60% below Opus 5). 5-minute cache write $5.Anthropic's comparison table lists Opus 5 at $5 input / $25 output and $0.50 cache reads per 1M.
Operational riskFour breaking changes versus Opus 5, including thinking that cannot be disabled and rejection of computer_20251124 on the Claude API and Google Cloud.Staying on Opus 5 avoids the migration, but you pay the higher published rates and miss the speed claim.

Key insights

Concrete technical or product signals.

  • Anthropic's price table is the source for the Opus 5 $5/$25 and $0.50 cache-read figures, not a guessed discount.
  • The 40% typical-cost claim is Anthropic's workload test at default settings, not a guarantee for every prompt.
  • Early-tester anecdotes, including the 680,000-line migration, are vendor stories, not a benchmark.

Use cases

Where this shines in production.

  • Upgrading claude-opus-5
  • Estimating the cache-read cut
  • Planning the thinking-block migration

Limitations & trade-offs

What to watch for.

  • Not a Fable or Sonnet comparison.
  • Batch 300K output requires the documented beta header.
  • Do not treat the 40% cost claim as your invoice.

Watch-outs

Who should pass, and what to validate before rollout.

  • Do not stay on Opus 5 for new work just to avoid a prompt change.
  • Do not cut over clients that still send computer_20251124 on the Claude API or Google Cloud.
  • Do not treat the 40% cost claim as a guaranteed discount.

Final recommendation

What to do after reading the table.

Move new Opus routes to Opus 5.5 after a replay. Keep Opus 5 only where the breaking changes still block you.

FAQ

Is Claude Opus 5.5 better than Claude Opus 5?

Neither Claude Opus 5.5 nor Claude Opus 5 is a universal winner. Use the comparison table and the choose-when notes, then validate on your workload.

Which is better for coding: Claude Opus 5.5 or Claude Opus 5?

Claude Opus 5.5: Anthropic reports large gains versus Opus 5 on long coding jobs and says a 680,000-line migration finished in under a day in one early test. Claude Opus 5: Prior Opus agent default. Anthropic's new table shows lower coding and computer-use scores than Opus 5.5. The catalog does not declare a winner on coding and agents.

Which is cheaper: Claude Opus 5.5 or Claude Opus 5?

Listed unit prices: Claude Opus 5.5 $4 / $20. Cache read $0.20 (60% below Opus 5). 5-minute cache write $5; Claude Opus 5 Anthropic's comparison table lists Opus 5 at $5 input / $25 output and $0.50 cache reads per 1M. A lower listed unit price is not the same as a lower total workload cost—tokens, session minutes, caching, introductory rates, and add-on modes can reverse the ranking. Confirm live rates on each vendor’s official page.

Can I use both Claude Opus 5.5 and Claude Opus 5?

Yes. Many teams keep both and route by constraint. Use Claude Opus 5.5 for Current Opus-tier agents, coding migrations, and knowledge work, and Claude Opus 5 for Pinned Opus 5 clients until they absorb the Opus 5.5 breaking changes. Confirm vendor terms before mixing them in one production workflow.

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Official sources

This page is based on publicly available documentation, benchmarks, and real-world usage patterns. Last reviewed for accuracy recently.