Claude Opus 4 series
by Anthropic
Entry point for Anthropic’s Opus 4 generation. Version notes carry the detail; this page tracks the line.
Versions
| Version | Note | Notes |
|---|---|---|
| Opus 4 | claude-opus-4 | Generation opener |
| Opus 4.1 | claude-opus-4-dot-1 | |
| Opus 4.5 | claude-opus-4-dot-5 | |
| Opus 4.6 | claude-opus-4-dot-6 | + adaptive reasoning |
| Opus 4.7 | claude-opus-4-dot-7 | ~3 months as frontier reference |
| Opus 4.8 | claude-opus-4-dot-8 | The benchmark target of mid-2026 |
Successors and siblings
- claude-opus-5 — next generation
- Claude Fable 5 · Claude Mythos — parallel Anthropic lines
- Sonnet 4.5 / 4.6 · Haiku 4.5 — tier siblings
Pattern
Opus 4.x shipped six point releases across roughly 18 months. Through mid-2026 the line served
as the industry’s frontier reference — open-weight releases were routinely marketed as matching
or beating the current Opus at a fraction of the cost. By August 2026 that comparison had become
routine enough that price and local runnability, not capability, were the differentiators.