Model comparison
Claude Mythos 5.1 vs Claude Fable 5
- Input
- $10.00
- Output
- $50.00
- Context
- 1M
- Released
- 2026-09-01
- Input
- $10.00
- Output
- $50.00
- Context
- 1M
- Released
- 2026-06-09
Both charge the same $10 per 1M input tokens.
Specs and pricing side by side
| Spec | Claude Mythos 5.1 | Claude Fable 5 |
|---|---|---|
| Maker | Anthropic | Anthropicsame |
| Released | 2026-09-01 | 2026-06-09 |
| Context window | 1M | 1Msame |
| Max output | 128K | 128Ksame |
| Input price | $10.00 | $10.00same |
| Output price | $50.00 | $50.00same |
| Parameters | Undisclosed | Undisclosedsame |
| License | Proprietary | Proprietarysame |
| Weights | API only | API onlysame |
| Modalities | Text, Vision | Text, Visionsame |
Not published by either maker: knowledge cutoff.
Benchmarks both models report
These two models have no benchmark in common in our registry, so there is no like-for-like score to compare. See each model’s own results: Claude Mythos 5.1, Claude Fable 5.
Which one should you pick?
Pick Claude Mythos 5.1 if…
- Your use case is: run defensive cybersecurity work, including identifying software vulnerabilities, inside a verified organization.
Pick Claude Fable 5 if…
- Your use case is: reach for it for the most demanding multi-step agentic coding across large codebases when you want above-Opus capability.
FAQ
Which is better, Claude Mythos 5.1 or Claude Fable 5?
Both charge the same $10 per 1M input tokens. The better pick depends on whether you value benchmark scores, price per token, context length or openness for your workload.
How do Claude Mythos 5.1 and Claude Fable 5 pricing compare?
Claude Mythos 5.1: $10.00 input, $50.00 output. Claude Fable 5: $10.00 input, $50.00 output (list API prices as published by each maker).
What are the context windows of Claude Mythos 5.1 and Claude Fable 5?
Claude Mythos 5.1 offers 1M with up to 128K output; Claude Fable 5 offers 1M with up to 128K output.
Is Claude Mythos 5.1 newer than Claude Fable 5?
Claude Mythos 5.1 was released 2026-09-01; Claude Fable 5 was released 2026-06-09.