WhichAI.todayClaude Fable 5.2
Anthropic
Pick this for the most difficult graduate-level reasoning, advanced proofs, and scientific research.
Skip it for everyday questions or routine math where standard models are faster and cheaper.
Humanity's Last Exam 74.3%.
Claude Fable 5.2 vs Kimi K3.1 Pro
Updated Nov 13, 2026. Checked daily.
The short answer
Claude Fable 5.2 ranks ahead in every job we track where either appears (reasoning, math & science).
Claude Fable 5.2
1 of 1 job ahead
Paid plan
Kimi K3.1 Pro
0 of 1 job ahead
Free (limited)
Head to head, job by job
Each job ranks a #1, an alternative, and an open-weights pick from public leaderboards. Bars compare the two scores on that job's own signal.
Claude Fable 5.2Kimi K3.1 Pro
Which one should you pick?
Kimi K3.1 Pro
Moonshot AI
Pick this when the problem cannot leave your own machines.
Skip it if you lack multi-GPU cluster hardware to host massive parameter weights locally.
Humanity's Last Exam 52.5%.
Price, access, and privacy
Claude Fable 5.2Kimi K3.1 Pro
Cost
Pro is $20/month, or $17 if billed yearly. API is $8 per million input tokens and $40 per million output.
Weights are free to download. API is $2 per million input tokens and $10 per million output.
Free tier
Not on the free plan. Fable requires a paid plan or API access.
The weights are free to download and run locally, and Kimi.ai offers limited free chat.
Where to get it
Trains on chats
Anthropic says Free, Pro, and Max chats are used for training only if you allow it, and you choose at signup. The toggle has been reported as on by default, so check it. Settings, then Privacy. Turn off Help improve Claude.
Yes. The Kimi consumer policy says prompts and files can be used to improve models. Ask Kimi support to stop training use if the app has no toggle.
Try both with the same prompt
Claude Fable 5.2
Solve this step by step, citing theorems used and highlighting any potential edge cases.
Kimi K3.1 Pro
Explain this concept with one example, then give me a harder practice problem.
Want a sharper prompt? Build one for either model.
Ranking history
- Nov 12, 2026. Claude Fable 5.2 overtook Claude Opus 5.5. Humanity's Last Exam 74.3%.
Questions
Is Claude Fable 5.2 or Kimi K3.1 Pro better for reasoning, math & science?
Claude Fable 5.2 ranks ahead for reasoning, math & science on Humanity's Last Exam. Claude Fable 5.2 is the #1 pick (74.3); Kimi K3.1 Pro is the open weights pick (52.5).
Which is cheaper, Claude Fable 5.2 or Kimi K3.1 Pro?
Claude Fable 5.2: Pro is $20/month, or $17 if billed yearly. API is $8 per million input tokens and $40 per million output. Kimi K3.1 Pro: Weights are free to download. API is $2 per million input tokens and $10 per million output.
Can I use Claude Fable 5.2 or Kimi K3.1 Pro for free?
Claude Fable 5.2: Not on the free plan. Fable requires a paid plan or API access. Kimi K3.1 Pro: The weights are free to download and run locally, and Kimi.ai offers limited free chat.
Which is more private, Claude Fable 5.2 or Kimi K3.1 Pro?
Claude Fable 5.2 (Anthropic): Anthropic says Free, Pro, and Max chats are used for training only if you allow it, and you choose at signup. The toggle has been reported as on by default, so check it. Kimi K3.1 Pro (Moonshot AI): Yes. The Kimi consumer policy says prompts and files can be used to improve models.