Model comparison
Kimi K2.5 (Reasoning) vs Step 3.7 Flash
Head-to-head evidence from 22 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
BenchAlign evidence: Kimi K2.5 (Reasoning) estimated; Step 3.7 Flash estimated. Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Kimi K2.5 (Reasoning) and Step 3.7 Flash share 22 comparable benchmark results. 2 of 8 categories are comparable. 6 results are unique to Kimi K2.5 (Reasoning); 8 to Step 3.7 Flash.
Updated July 16, 2026- Shared results
- 22
- Kimi K2.5 (Reasoning) only
- 6
- Step 3.7 Flash only
- 8
- Comparable categories
- 2 / 8
Pick Kimi K2.5 (Reasoning) if you want the stronger benchmark profile. Step 3.7 Flash only becomes the better choice if agentic is the priority or you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 22 shared benchmark results across 6 evidence categories; 2 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 provisional aggregate, 70 to 57. 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 coding, where it averages 76.8 against 56.3. The single biggest benchmark swing on the page is BrowseComp, 60.6% to 75.8%. Step 3.7 Flash does hit back in agentic, so the answer changes if that is the part of the workload you care about most.
Kimi K2.5 (Reasoning) is also the more expensive model on tokens at $0.60 input / $3.00 output per 1M tokens, versus $0.20 input / $1.15 output per 1M tokens for Step 3.7 Flash. That is roughly 2.6x on output cost alone. Step 3.7 Flash gives you the larger context window at 256K, 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 | Step 3.7 Flash |
|---|---|---|---|
| Coding | Kimi K2.5 (Reasoning)76.8 | Margin← 20.5 | Step 3.7 Flash56.3 |
| Agentic | Kimi K2.5 (Reasoning)55.0 | Margin→ 11.4 | Step 3.7 Flash66.4 |
| Knowledge | Kimi K2.5 (Reasoning)87.2 | MarginNo overlap | Step 3.7 FlashNot measured |
| Multimodal | Kimi K2.5 (Reasoning)78.5 | MarginNo overlap | Step 3.7 FlashNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
BrowseComp
AgenticA 60.6%B 75.8%Winner: Step 3.7 FlashΔ 15.2BrowseComp: Kimi K2.5 (Reasoning) scored 60.6%; Step 3.7 Flash scored 75.8%. Step 3.7 Flash wins this benchmark. - Source ↗
Terminal-Bench 2.0
AgenticA 50.8%B 59.5%Winner: Step 3.7 FlashΔ 8.7Terminal-Bench 2.0: Kimi K2.5 (Reasoning) scored 50.8%; Step 3.7 Flash scored 59.5%. Step 3.7 Flash 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) | Step 3.7 Flash | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Kimi K2.5 (Reasoning)$0.6 input / $3 output | Step 3.7 Flash$0.2 input / $1.15 output | Step 3.7 Flash has the lower combined listed price. |
| Generation speedtokens per second | Kimi K2.5 (Reasoning)Not available | Step 3.7 FlashNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Kimi K2.5 (Reasoning)Not available | Step 3.7 FlashNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Kimi K2.5 (Reasoning)128K | Step 3.7 Flash256K | Step 3.7 Flash lists the larger context window. |
Benchmark Deep Dive
AgenticStep 3.7 Flash wins12 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | Step 3.7 Flash | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 50.8% | 59.5% | Step 3.7 Flash leads |
| BrowseCompSource | 60.6% | 75.8% | Step 3.7 Flash leads |
| APEX-Agents-AASource | 11.5% | 14.8% | Step 3.7 Flash leads |
| τ²-bench resultsSource | 95.9% | 98.5% | Step 3.7 Flash leads |
| Gert LabsSource | 32.58% | 51.57% | Step 3.7 Flash leads |
| AA Agentic IndexSource | 21.7% | 21.5% | Kimi K2.5 (Reasoning) leads |
| GDPval-AASource | 25.4% | 25.9% | Step 3.7 Flash leads |
| GDPval-AASource | 1009 | 1017 | Step 3.7 Flash leads |
| DeepSearchQASource | — | 92.8% | Not comparable |
| ToolathlonSource | — | 49.5% | Not comparable |
| Claw-EvalSource | — | 67.1% | Not comparable |
| HLE w/ toolsSource | — | 47.2% | Not comparable |
CodingKimi K2.5 (Reasoning) wins7 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | Step 3.7 Flash | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 76.8% | — | Not comparable |
| Vibe Code BenchSource | 17.54% | — | Not comparable |
| Terminal-Bench HardSource | 34.8% | 35.6% | Step 3.7 Flash leads |
| AA-SciCodeSource | 49.0% | 40.0% | Kimi K2.5 (Reasoning) leads |
| AA Coding IndexSource | 46.8% | 39.6% | Kimi K2.5 (Reasoning) leads |
| SWE-bench ProSource | — | 56.3% | Not comparable |
| Terminal-Bench 2.0Source | — | 59.5% | Not comparable |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | Step 3.7 Flash | Result |
|---|---|---|---|
| GPQASource | 87.6% | — | Not comparable |
| MMLU-ProSource | 87.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 35.4% | 30.3% | Kimi K2.5 (Reasoning) leads |
| AA-GPQA DiamondSource | 87.9% | 80.9% | Kimi K2.5 (Reasoning) leads |
| AA-HLESource | 29.4% | 19.9% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience IndexSource | -8.1% | -37.5% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience AccuracySource | 34.3% | 25.4% | Kimi K2.5 (Reasoning) leads |
| AA-Omniscience Hallucination RateSource | 64.6% | 84.4% | Kimi K2.5 (Reasoning) leads |
Math1 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | Step 3.7 Flash | Result |
|---|---|---|---|
| AIME 2025Source | 96.1% | — | Not comparable |
Multimodal5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Kimi K2.5 (Reasoning) | Step 3.7 Flash | Result |
|---|---|---|---|
| AA-IFBenchSource | 70.2% | 67.3% | Kimi K2.5 (Reasoning) leads |
Frequently Asked Questions (3)
Which is better, Kimi K2.5 (Reasoning) or Step 3.7 Flash?
Kimi K2.5 (Reasoning) is ahead on BenchLM's provisional leaderboard, 70 to 57. The biggest single separator in this matchup is BrowseComp, where the scores are 60.6% and 75.8%.
Which is better for coding, Kimi K2.5 (Reasoning) or Step 3.7 Flash?
Kimi K2.5 (Reasoning) has the edge for coding in this comparison, averaging 76.8 versus 56.3. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, Kimi K2.5 (Reasoning) or Step 3.7 Flash?
Step 3.7 Flash has the edge for agentic tasks in this comparison, averaging 66.4 versus 55. Inside this category, Gert Labs is the benchmark that creates the most daylight between them.
Related Comparisons
The AI models change fast. We track them for you.
A weekly brief for engineers and researchers covering new models, ranking shifts, and pricing changes.
Free. No spam. Unsubscribe anytime.