Claude Opus 4
claude-opus-4-20250514
buried here: claude-opus-4-20250514
2025-05-22 — 2026-06-15 · lived 1 year
The large half of the generation that made Claude a coding model first and everything else second: sustained work measured in hours rather than answers measured in seconds, which is the shape every agent took afterwards. Thirteen months, and then the same funeral as Sonnet 4. Anthropic kept the weights; what closed was the endpoint.
- Provider
- Anthropic
- Cause of death
- Superseded
- Notice given
- 2026-04-14
- Succeeded by
- Claude Opus 4.1
“Succeeded by” is this site’s reading of model lineage, not the provider’s official migration guidance.