# Kimi K2.5 vs Step 3.7 Flash

> Kimi K2.5 is the stronger model overall, scoring 47.8 to 36.5 on the Noometry Index. Step 3.7 Flash costs 2.2× less per token, which makes it the better buy when Kimi K2.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/kimi-k2-5-vs-step-3-7-flash
- Last updated: 2026-10-10
- Shared benchmarks: 5

## Summary

- They share 5 benchmarks with published results for both. Kimi K2.5 scores higher in 3 categories and Step 3.7 Flash in 0 categories; 3 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Kimi K2.5 leads 31.2 to 20.9.
- The biggest single-benchmark swing is NYT Connections (extended): 69.9% for Kimi K2.5 and 39.7% for Step 3.7 Flash.
- Step 3.7 Flash is cheaper at $0.18 / $1.11 per million input/output tokens, against $0.45 / $2.25 for Kimi K2.5.
- Kimi K2.5 accepts more context: 262K tokens versus 256K.

## Snapshot

| | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| Provider | Moonshot AI | StepFun |
| Noometry Index | 47.8 | 36.5 |
| Rank | 50 | 207 |
| Context | 262K | 256K |
| Input $/M | $0.45 | $0.18 |
| Output $/M | $2.25 | $1.11 |
| Weights | Open | Open |

## Coding

- Kimi K2.5: 48.7 (#48)
- Step 3.7 Flash: 39.4 (#147)

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| SciCode | 49% | 40% |
| ALE-Bench | 821.65 | 694.12 |
| SWE-bench Verified | 73.8% | — |
| SWE-bench Verified (bash only) | 70.8% | — |
| LMArena WebDev | 1436 | — |
| SWE-bench Multilingual | 67.3% | — |
| WeirdML | 45.6% | — |
| LMArena Coding | 1474 | — |

## Agentic & Tool Use

- Kimi K2.5: 34.0 (#44)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| Terminal-Bench | 43.2% | — |
| OSWorld | 63.3% | — |
| Vending-Bench 2 | 1,198 | — |

## Reasoning

- Kimi K2.5: 31.2 (#74)
- Step 3.7 Flash: 20.9 (#211)

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| NYT Connections (extended) | 69.9% | 39.7% |
| CritPt | 3.1% | 2.3% |
| ARC-AGI-2 | 11.8% | — |
| SimpleBench | 46.8% | — |
| Kagi LLM Benchmark | 78.5% | — |
| ARC-AGI-1 | 65.3% | — |
| Chess Puzzles | 12% | — |
| EnigmaEval | 3.4% | — |
| Thematic Generalization | 69.4% | — |
| LMArena Hard Prompts | 1454 | — |
| Epoch Capabilities Index | 148.05 | — |

## Math

- Kimi K2.5: 50.3 (#46)
- Step 3.7 Flash: 40.9 (#74)

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| MathArena Final-Answer Competitions | 62.3% | 68.5% |
| OTIS Mock AIME 2024-2025 | 92.2% | — |
| LMArena Math | 1470 | — |
| FrontierMath (Feb 2025 set) | 27.9% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |

## Knowledge

- Kimi K2.5: 53.6 (#52)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| GPQA Diamond | 87.6% | — |
| Humanity's Last Exam | 24.4% | — |
| SimpleQA Verified | 34.3% | — |
| Vectara Hallucination Rate | 14.2% | — |
| LMArena Expert | 1466 | — |

## Multimodal

- Kimi K2.5: 40.4 (#37)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| LMArena Vision | 1269 | — |
| LMArena Document | 1430 | — |

## Multilingual

- Kimi K2.5: 54.1 (#50)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| LMArena Non-English | 1433 | — |
| LMArena Chinese | 1495 | — |
| LMArena French | 1454 | — |
| LMArena German | 1441 | — |
| LMArena Japanese | 1422 | — |
| LMArena Korean | 1412 | — |
| LMArena Russian | 1436 | — |
| LMArena Spanish | 1450 | — |

## Instruction Following

- Kimi K2.5: 75.5 (#60)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| LMArena Instruction Following | 1431 | — |

## Long Context

- Kimi K2.5: 52.1 (#7)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| Fiction.LiveBench | 86.1% | — |
| CL-bench | 19.3% | — |
| CL-bench Life | 13.2% | — |
| LMArena Longer Query | 1445 | — |

## Writing & Preference

- Kimi K2.5: 65.3 (#51)
- Step 3.7 Flash: —

| Benchmark | Kimi K2.5 | Step 3.7 Flash |
|---|---|---|
| LMArena Text | 1445 | — |
| LMArena Creative Writing | 1423 | — |
| EQ-Bench Creative Writing | 1579 | — |
| LMArena Multi-Turn | 1444 | — |

## FAQ

### Is Kimi K2.5 better than Step 3.7 Flash?

Kimi K2.5 is the stronger model overall, scoring 47.8 to 36.5 on the Noometry Index. Step 3.7 Flash costs 2.2× less per token, which makes it the better buy when Kimi K2.5's lead doesn't matter for your workload.

### Which is cheaper, Kimi K2.5 or Step 3.7 Flash?

Step 3.7 Flash is cheaper. It lists at $0.18 per million input tokens and $1.11 per million output tokens; Kimi K2.5 lists at $0.45 and $2.25.

### Is Kimi K2.5 or Step 3.7 Flash better for coding?

Kimi K2.5 scores higher on coding benchmarks: 48.7 versus 39.4 in the Noometry coding category.

### Which has the bigger context window?

Kimi K2.5 does, with 262K tokens against 256K.

### How many benchmarks do Kimi K2.5 and Step 3.7 Flash share?

5 benchmarks have published results for both models. Kimi K2.5 has 51 scored results on Noometry and Step 3.7 Flash has 5.