PyyanThe AI Index

Pyyan / Compare / Claude Opus 4.5 vs Claude Sonnet 5

Claude Opus 4.5 vs Claude Sonnet 5

2 of 5

Language Models · verified 13 Aug 2026

Claude Opus 4.5Anthropicdeprecated
Claude Sonnet 5Anthropiccurrent
3 slots left
SpecificationClaude Opus 4.5Claude Sonnet 5
SummaryLegacy Opus, still callable.Near-Opus quality on coding and agentic work at Sonnet cost.
Context—1M
Input ($/Mtok)—$3
Output ($/Mtok)—$15
LicenceProprietaryProprietary
Max output—128K
Model IDclaude-opus-4-5claude-sonnet-5
CategoryLanguage ModelsLanguage Models
OfficialAnthropic ↗Anthropic ↗

Highlighted rows are where these differ.

Claude Opus 4.5

Legacy Opus, still callable.

Best for pinned workloads.

Full spec sheet →

Claude Sonnet 5

  • Adaptive thinking on by default
  • New tokenizer — roughly 30% more tokens for the same text
  • Introductory $2/$10 through 31 Aug 2026

Best for high-volume production.

Full spec sheet →