Claude Opus 5.5 is the model Anthropic recommends starting with for most workloads, especially long-running agentic coding and knowledge work. It has a 1M-token context window and always-on adaptive thinking.
Claude Opus 5.5
Anthropic's default model for agentic coding and knowledge work
Checked 2026-11-12 against Anthropic's documentation
| Provider | Anthropic |
| Status | Current |
| Context window | 1M tokens |
| Pricing | Paid |
| Input price | $4.00/M |
| Output price | $20.00/M |
| Capabilities | textvisioncodefunction-callingreasoning |
| API docs | Docs ↗ |
Benchmarks
Benchmark data not yet available for this model.
Compare with similar models
| Claude Opus 5.5 | Claude Opus 4.6 | Gemini 2.5 Pro | Claude Fable 5.2 | |
|---|---|---|---|---|
| Context | 1M | 200K | 1.05M | 1M |
| MMLU | — | 92.0 | 91.0 | — |
| HumanEval | — | 94.5 | — | — |
| MATH | — | 97.1 | 97.0 | — |
| GPQA | — | 79.9 | 84.0 | — |
| Pricing | Paid | Paid | Paid | Paid |
| Input $/M | $4.00 | $15.00 | $1.25 | $8.00 |