Model comparison
Kimi K2.5 (Reasoning) vs o1
Head-to-head evidence from 13 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Kimi K2.5 (Reasoning) #63 (Estimated); o1 #136 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Kimi K2.5 (Reasoning) and o1 share 13 comparable benchmark results. 1 of 8 categories are comparable. 14 results are unique to Kimi K2.5 (Reasoning); 3 to o1.
Updated July 24, 2026- Shared results
- 13
- Kimi K2.5 (Reasoning) only
- 14
- o1 only
- 3
- Comparable categories
- 1 / 8
Pick Kimi K2.5 (Reasoning) if you want the stronger benchmark profile. o1 only becomes the better choice if you need the larger 200K context window.
Confidence note. This is a partial-evidence comparison with 13 shared benchmark results across 5 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Kimi K2.5 (Reasoning) is clearly ahead on the BenchAlign aggregate, 58.61 to 47.14. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Kimi K2.5 (Reasoning)'s sharpest advantage is in knowledge, where it averages 87.2 against 75.7. The single biggest benchmark swing on the page is GPQA, 87.6% to 75.7%.
o1 is also the more expensive model on tokens at $15.00 input / $60.00 output per 1M tokens, versus $0.60 input / $3.00 output per 1M tokens for Kimi K2.5 (Reasoning). That is roughly 20.0x on output cost alone. o1 gives you the larger context window at 200K, 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 | Kimi K2.5 (Reasoning) | Δ | o1 |
|---|---|---|---|
| Knowledge | Kimi K2.5 (Reasoning)87.2 | Margin← 11.5 | o175.7 |
| Agentic | Kimi K2.5 (Reasoning)55.0 | MarginNo overlap | o1Not measured |
| Coding | Kimi K2.5 (Reasoning)76.8 | MarginNo overlap | o1Not measured |
| Math | Kimi K2.5 (Reasoning)Not measured | MarginNo overlap | o19.3 |
| Multimodal | Kimi K2.5 (Reasoning)78.5 | MarginNo overlap | o1Not measured |
| Inst. Following | Kimi K2.5 (Reasoning)Not measured | MarginNo overlap | o192.2 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
GPQA
KnowledgeA 87.6%B 75.7%Winner: Kimi K2.5 (Reasoning)Δ 11.9GPQA: Kimi K2.5 (Reasoning) scored 87.6%; o1 scored 75.7%. Kimi K2.5 (Reasoning) wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Kimi K2.5 (Reasoning) | o1 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Kimi K2.5 (Reasoning)$0.6 input / $3 output | o1$15 input / $60 output | Kimi K2.5 (Reasoning) has the lower combined listed price. |
| Generation speedtokens per second | Kimi K2.5 (Reasoning)Not available | o198 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Kimi K2.5 (Reasoning)Not available | o132.29 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Kimi K2.5 (Reasoning)128K | o1200K | o1 lists the larger context window. |
Benchmark Deep Dive
Agentic8 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | o1 | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 50.8% | — | Not comparable |
| BrowseCompSource | 60.6% | — | Not comparable |
| APEX-Agents-AASource | 11.5% | — | Not comparable |
| τ²-bench resultsSource | 95.9% | 62.6% | Kimi K2.5 (Reasoning) leads |
| Gert LabsSource | 32.58% | — | Not comparable |
| AA Agentic IndexSource | 21.7% | — | Not comparable |
| GDPval-AASource | 25.1% | — | Not comparable |
| GDPval-AASource | 1003 | — | Not comparable |
Coding4 benchmarks
Reasoning2 benchmarks
KnowledgeKimi K2.5 (Reasoning) wins9 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | o1 | Result |
|---|---|---|---|
| GPQASource | 87.6% | 75.7% | Kimi K2.5 (Reasoning) leads |
| MMLU-ProSource | 87.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 35.4% | 23.4% | Kimi K2.5 (Reasoning) leads |
| AA-GPQA DiamondSource | 87.9% | 74.7% | Kimi K2.5 (Reasoning) leads |
| AA-HLESource | 29.4% | 7.7% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience IndexSource | -8.1% | -10.5% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience AccuracySource | 34.3% | 34.7% | o1 leads |
| AA-Omniscience Hallucination RateSource | 64.6% | 69.3% | Kimi K2.5 (Reasoning) leads |
| MMLUSource | — | 91.8% | Not comparable |
Math2 benchmarks
Multimodal3 benchmarks
Frequently Asked Questions (2)
Which is better, Kimi K2.5 (Reasoning) or o1?
Kimi K2.5 (Reasoning) is ahead on BenchLM's BenchAlign leaderboard, 58.61 to 47.14. The biggest single separator in this matchup is GPQA, where the scores are 87.6% and 75.7%.
Which is better for knowledge tasks, Kimi K2.5 (Reasoning) or o1?
Kimi K2.5 (Reasoning) has the edge for knowledge tasks in this comparison, averaging 87.2 versus 75.7. Inside this category, AA-HLE is the benchmark that creates the most daylight between them.