Claude Models Guide: Choosing Opus 5 or Sonnet 5 | XTIANZ

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CLAUDE MODELS

CL5

On this page

Current model positioning
When Opus 5 makes sense
When Sonnet 5 is the better default
A practical routing pattern
Evaluation checklist
What to watch next

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Reviewed July 29, 2026 · Educational content · Primary-source links for changing claims.

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