AnthropicClaude Mythos 5.1
Claude Mythos 5.1 is an Anthropic proprietary reasoning model. It is not yet ranked: no independent benchmark results so far, only pricing and metadata. At $20.00 per million tokens blended it is among the most expensive ranked models.
- Blended price
- $20.00/M
- $10.00 in · $50.00 out
- Output speed
- –
- First answer
- –
- Context
- 1M
- Full answer
- –
- Cost per run
- –
- Released
- –
- date not published by our sources
No independent quality benchmark results yet — only pricing and metadata.
What a task costs
Estimates from list price, output speed and time to first answer for the best configuration. “With caching” assumes three-quarters of the input is served from the prompt cache. Reasoning tokens are not modelled.
| Workload | Tokens in / out | Cost | With caching | Time |
|---|---|---|---|---|
| Chat reply | 400 / 300 | $0.019 | – | – |
| Summarize a 30-page report | 12,000 / 600 | $0.150 | – | – |
| Code edit | 6,000 / 1,500 | $0.135 | – | – |
| Agentic coding session | 60,000 / 4,000 | $0.800 | – | – |
| Structured extraction | 2,000 / 200 | $0.030 | – | – |
More from Anthropic
See also
Questions people ask
- Why does Claude Mythos 5.1 have no BenchLeader Index score?
- The index needs at least five independent results across at least two categories; as of 25 Oct 2026 Claude Mythos 5.1 has 0 that count. Launch-post scores are never used, so it is ranked once independent publishers have measured it.
- How much does Claude Mythos 5.1 cost per 1M tokens?
- As of 25 Oct 2026, Claude Mythos 5.1 costs $10.00 per 1M input tokens and $50.00 per 1M output tokens, $20.00 blended (three input tokens per output token).
Data as of 25 Oct 2026. Compare with another model.
Cite as: BenchLeader, “Claude Mythos 5.1: benchmarks, pricing, speed and rank”, data as of 25 Oct 2026, https://www.benchleader.com/models/claude-mythos-5-1.