Model comparison
Claude Fable 5 vs Kimi K2.5 (Reasoning)
Head-to-head evidence from 18 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Fable 5 #2 (Supported); Kimi K2.5 (Reasoning) #57 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Fable 5 and Kimi K2.5 (Reasoning) share 18 comparable benchmark results. 3 of 8 categories are comparable. 16 results are unique to Claude Fable 5; 9 to Kimi K2.5 (Reasoning).
Updated July 23, 2026- Shared results
- 18
- Claude Fable 5 only
- 16
- Kimi K2.5 (Reasoning) only
- 9
- Comparable categories
- 3 / 8
Pick Claude Fable 5 if you want the stronger benchmark profile. Kimi K2.5 (Reasoning) only becomes the better choice if multimodal & grounded is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 18 shared benchmark results across 6 evidence categories; 3 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Fable 5 is clearly ahead on the BenchAlign aggregate, 83.68 to 59.35. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Fable 5's sharpest advantage is in agentic, where it averages 84.6 against 55. The single biggest benchmark swing on the page is Terminal-Bench 2.0, 84.3% to 50.8%. Kimi K2.5 (Reasoning) does hit back in multimodal & grounded, so the answer changes if that is the part of the workload you care about most.
Claude Fable 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $0.60 input / $3.00 output per 1M tokens for Kimi K2.5 (Reasoning). That is roughly 16.7x on output cost alone. Claude Fable 5 gives you the larger context window at 1M+, compared with 128K for Kimi K2.5 (Reasoning).
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Fable 5 | Δ | Kimi K2.5 (Reasoning) |
|---|---|---|---|
| Agentic | Claude Fable 584.6 | Margin← 29.6 | Kimi K2.5 (Reasoning)55.0 |
| Multimodal | Claude Fable 557.9 | Margin→ 20.6 | Kimi K2.5 (Reasoning)78.5 |
| Coding | Claude Fable 589.2 | Margin← 12.4 | Kimi K2.5 (Reasoning)76.8 |
| Knowledge | Claude Fable 5Not measured | MarginNo overlap | Kimi K2.5 (Reasoning)87.2 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
Terminal-Bench 2.0
AgenticA 84.3%B 50.8%Winner: Claude Fable 5Δ 33.5Terminal-Bench 2.0: Claude Fable 5 scored 84.3%; Kimi K2.5 (Reasoning) scored 50.8%. Claude Fable 5 wins this benchmark. - Source ↗
SWE-bench Verified
CodingA 95%B 76.8%Winner: Claude Fable 5Δ 18.2SWE-bench Verified: Claude Fable 5 scored 95%; Kimi K2.5 (Reasoning) scored 76.8%. Claude Fable 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Fable 5 | Kimi K2.5 (Reasoning) | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Fable 5$10 input / $50 output | Kimi K2.5 (Reasoning)$0.6 input / $3 output | Kimi K2.5 (Reasoning) has the lower combined listed price. |
| Generation speedtokens per second | Claude Fable 5Not available | Kimi K2.5 (Reasoning)Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Fable 5Not available | Kimi K2.5 (Reasoning)Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Fable 51M+ | Kimi K2.5 (Reasoning)128K | Claude Fable 5 lists the larger context window. |
Benchmark Deep Dive
AgenticClaude Fable 5 wins16 benchmarks
| Benchmark | Claude Fable 5 | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 84.3% | 50.8% | Claude Fable 5 leads |
| OSWorld-VerifiedSource | 85% | — | Not comparable |
| GDPval-AASource | 1748 | 1009 | Claude Fable 5 leads |
| AA Agentic IndexSource | 52.8% | 21.7% | Claude Fable 5 leads |
| τ²-bench resultsSource | 98.5% | 95.9% | Claude Fable 5 leads |
| GDPval-AASource | 62.4% | 25.4% | Claude Fable 5 leads |
| AA BriefcaseSource | 1574 | — | Not comparable |
| AA AutomationBenchSource | 48.6% | — | Not comparable |
| AA EnterpriseOps-GymSource | 51.1% | — | Not comparable |
| AA Harvey LABSource | 93.6% | — | Not comparable |
| AA Tau3 BankingSource | 26.8% | — | Not comparable |
| terminalBenchHardSource | 62.9% | — | Not comparable |
| aaTerminalBench21Source | 84.6% | — | Not comparable |
| BrowseCompSource | — | 60.6% | Not comparable |
| APEX-Agents-AASource | — | 11.5% | Not comparable |
| Gert LabsSource | — | 32.58% | Not comparable |
CodingClaude Fable 5 wins10 benchmarks
| Benchmark | Claude Fable 5 | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95% | 76.8% | Claude Fable 5 leads |
| SWE-bench ProSource | 80% | — | Not comparable |
| FrontierCode 1.1 MainSource | 53.5% | — | Not comparable |
| Terminal-Bench 2.0Source | 84.3% | — | Not comparable |
| cursorBench31Source | 70.6% | — | Not comparable |
| cursorBench32Source | 70.5% | — | Not comparable |
| VulcanBench v3Source | 87.0% | — | Not comparable |
| AA Coding IndexSource | 76.5% | 46.8% | Claude Fable 5 leads |
| AA-SciCodeSource | 60.2% | 49.0% | Claude Fable 5 leads |
| Vibe Code BenchSource | — | 17.54% | Not comparable |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Claude Fable 5 | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 59.9% | 35.4% | Claude Fable 5 leads |
| AA-GPQA DiamondSource | 92.6% | 87.9% | Claude Fable 5 leads |
| AA-HLESource | 53.3% | 29.4% | Claude Fable 5 leads |
| AA-Omniscience IndexSource | 40.2% | -8.1% | Claude Fable 5 leads |
| AA-Omniscience AccuracySource | 61.4% | 34.3% | Claude Fable 5 leads |
| AA-Omniscience Hallucination RateSource | 54.9% | 64.6% | Claude Fable 5 leads |
| GPQASource | — | 87.6% | Not comparable |
| MMLU-ProSource | — | 87.1% | Not comparable |
Math1 benchmarks
| Benchmark | Claude Fable 5 | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| AIME 2025Source | — | 96.1% | Not comparable |
MultimodalKimi K2.5 (Reasoning) wins5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Fable 5 | Kimi K2.5 (Reasoning) | Result |
|---|---|---|---|
| AA-IFBenchSource | 63.5% | 70.2% | Kimi K2.5 (Reasoning) leads |
Frequently Asked Questions (4)
Which is better, Claude Fable 5 or Kimi K2.5 (Reasoning)?
Claude Fable 5 is ahead on BenchLM's BenchAlign leaderboard, 83.68 to 59.35. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 84.3% and 50.8%.
Which is better for coding, Claude Fable 5 or Kimi K2.5 (Reasoning)?
Claude Fable 5 has the edge for coding in this comparison, averaging 89.2 versus 76.8. Inside this category, AA Coding Index is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, Claude Fable 5 or Kimi K2.5 (Reasoning)?
Claude Fable 5 has the edge for agentic tasks in this comparison, averaging 84.6 versus 55. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.
Which is better for multimodal and grounded tasks, Claude Fable 5 or Kimi K2.5 (Reasoning)?
Kimi K2.5 (Reasoning) has the edge for multimodal and grounded tasks in this comparison, averaging 78.5 versus 57.9. Inside this category, Design Arena Website is the benchmark that creates the most daylight between them.
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