Claude Fable 5.1 vs Kimi K3.
Verdict by category, tale of the tape, shared benchmarks only, and cost at three workloads — all from the tracked data.
Verdict by category
| Category | Claude Fable 5.1 | Kimi K3 | Winner |
|---|---|---|---|
| League Score | 97.3 | 70.6 | Claude Fable 5.1 |
| Coding (SWE-bench %) | — | — | — |
| Reasoning (GPQA %) | 93.7 | 93.5 | Claude Fable 5.1 |
| Context (tokens) | 1000000 | 1048576 | Kimi K3 |
| Speed (tok/s) | — | 44.8 | — |
| Price (blended $/1M) | $20.00 | $6.00 | Kimi K3 (cheaper) |
Tale of the tape
| Spec | Claude Fable 5.1 | Kimi K3 |
|---|---|---|
| Maker | Anthropic | Moonshot AI |
| Released | Sep 1, 2026 | Jul 16, 2026 |
| League Score | 97 | 71 |
| Context | 1,000,000 tokens | 1,048,576 tokens |
| Max output | 128,000 | 131,072 |
| $/1M input | $10.00 | $3.00 |
| $/1M output | $50.00 | $15.00 |
| Weights | Closed | Open |
| Speed | — | 44.8 t/s |
Head-to-head benchmarks (shared only)
| Benchmark | Claude Fable 5.1 | Kimi K3 |
|---|---|---|
| LiveBench overall | 85.7 | 64.6 |
| GPQA Diamond | 93.7 | 93.5 |
Cost at three workloads
| Workload | Claude Fable 5.1 | Kimi K3 |
|---|---|---|
| Light — 1M in / 250K out | $22.50 | $6.75 |
| Standard — 10M in / 2.5M out | $225.00 | $67.50 |
| Long-context — 50M in / 5M out | $750.00 | $225.00 |
The pick
Pick Claude Fable 5.1 if you want the higher overall League Score.
Pick Kimi K3 if you need the bigger context window; you want the lower running cost; you want downloadable weights / self-hosting.
All figures from the model database — sources and dates on each model page. Cost your own workload or compare a different pair.
Frequently asked questions
Which is better overall, Claude Fable 5.1 or Kimi K3?
Claude Fable 5.1 leads on overall League Score, 97 to 71 — a gap of 27 points on a composite of sourced benchmarks. That is overall form, not every category: check the per-category verdicts before choosing.
Which is cheaper, Claude Fable 5.1 or Kimi K3?
Kimi K3 is cheaper: $6.00 vs $20.00 blended per 1M tokens (3:1 input/output mix) — about 3.3x less per token.
Which has the bigger context window, Claude Fable 5.1 or Kimi K3?
Kimi K3, with 1M of context against 1M for Claude Fable 5.1.
Which is better at reasoning, Claude Fable 5.1 or Kimi K3?
Claude Fable 5.1 leads on GPQA Diamond, 93.7% vs 93.5% on graduate-level science questions.
Are Claude Fable 5.1 and Kimi K3 open source?
Claude Fable 5.1 is closed weights — API access only; Kimi K3 is open weights — it can be downloaded and self-hosted.