| Claude Fable 5 | Claude Mythos 5 | |
|---|---|---|
| arenaElo | 1492 | 1493 |
| humanEval | 98 | 98 |
| sweBench | 77 | 78 |
| mmlu | 95.1 | 95.1 |
| gpqa | 92 | 92 |
| aime | 94 | 94.5 |
| Price in/out ($/M) | $10 / $50 | $10 / $50 |
These are the same model on two access paths: identical capabilities, $10 / $50 per M tokens, 1M context, 128K output and always-on protected thinking. Fable 5 is generally available on the Claude API; Mythos 5 is the Project Glasswing successor to the Mythos Preview. Unless you are inside Project Glasswing, Fable 5 is the one you can actually ship on, and there is no capability you give up by choosing it.