# Kimi K2.5 vs Step 5 Preview

> Kimi K2.5 and Step 5 Preview score almost the same on the Noometry Index (48.1 vs 47.9), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/kimi-k2-5-vs-step-5-preview
- Last updated: 2026-10-10
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. Kimi K2.5 scores higher in 6 categories and Step 5 Preview in 3 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where Kimi K2.5 leads 53.6 to 41.2.
- The biggest single-benchmark swing is CritPt: 3.1% for Kimi K2.5 and 20.9% for Step 5 Preview.
- Kimi K2.5 is cheaper at $0.45 / $2.25 per million input/output tokens, against $1 / $2.70 for Step 5 Preview.
- Step 5 Preview accepts more context: 1.02M tokens versus 262K.
- Kimi K2.5 has downloadable open weights; the other is API-only.

## Snapshot

| | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| Provider | Moonshot AI | StepFun |
| Noometry Index | 48.1 | 47.9 |
| Rank | 57 | 58 |
| Context | 262K | 1.02M |
| Input $/M | $0.45 | $1 |
| Output $/M | $2.25 | $2.70 |
| Weights | Open | Proprietary |

## Coding

- Kimi K2.5: 48.8 (#53)
- Step 5 Preview: 51.8 (#36)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena WebDev | 1437 | 1564 |
| SciCode | 49% | 58.9% |
| LMArena Coding | 1474 | 1480 |
| SWE-bench Verified | 73.8% | — |
| SWE-bench Verified (bash only) | 70.8% | — |
| SWE-bench Multilingual | 67.3% | — |
| WeirdML | 45.6% | — |
| ALE-Bench | 821.65 | — |

## Agentic & Tool Use

- Kimi K2.5: 34.2 (#48)
- Step 5 Preview: —

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

## Reasoning

- Kimi K2.5: 31.2 (#80)
- Step 5 Preview: 40.0 (#57)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| CritPt | 3.1% | 20.9% |
| LMArena Hard Prompts | 1453 | 1465 |
| ARC-AGI-2 | 11.8% | — |
| SimpleBench | 46.8% | — |
| Kagi LLM Benchmark | 78.5% | — |
| NYT Connections (extended) | 69.9% | — |
| ARC-AGI-1 | 65.3% | — |
| Chess Puzzles | 12% | — |
| EnigmaEval | 3.4% | — |
| Thematic Generalization | 69.4% | — |
| Epoch Capabilities Index | 148.03 | — |

## Math

- Kimi K2.5: 51.8 (#53)
- Step 5 Preview: 46.1 (#72)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Math | 1470 | 1470 |
| MathArena Final-Answer Competitions | 62.3% | — |
| OTIS Mock AIME 2024-2025 | 92.2% | — |
| ProofBench | — | 42% |
| FrontierMath (Feb 2025 set) | 27.9% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |

## Knowledge

- Kimi K2.5: 53.6 (#56)
- Step 5 Preview: 41.2 (#112)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Expert | 1466 | 1470 |
| GPQA Diamond | 87.6% | — |
| Humanity's Last Exam | 24.4% | — |
| SimpleQA Verified | 34.3% | — |
| Vectara Hallucination Rate | 14.2% | — |

## Multimodal

- Kimi K2.5: 41.1 (#39)
- Step 5 Preview: 41.0 (#41)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Vision | 1269 | 1267 |
| LMArena Document | 1430 | — |

## Multilingual

- Kimi K2.5: 53.9 (#53)
- Step 5 Preview: 53.8 (#54)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Non-English | 1433 | 1432 |
| LMArena Chinese | 1495 | 1519 |
| LMArena Russian | 1435 | 1436 |
| LMArena Spanish | 1450 | 1439 |
| LMArena French | 1454 | — |
| LMArena German | 1441 | — |
| LMArena Japanese | 1421 | — |
| LMArena Korean | 1410 | — |

## Instruction Following

- Kimi K2.5: 75.3 (#64)
- Step 5 Preview: 76.0 (#50)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Instruction Following | 1431 | 1444 |

## Long Context

- Kimi K2.5: 52.1 (#7)
- Step 5 Preview: 44.5 (#64)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Longer Query | 1445 | 1455 |
| Fiction.LiveBench | 86.1% | — |
| CL-bench | 19.3% | — |
| CL-bench Life | 13.2% | — |

## Writing & Preference

- Kimi K2.5: 65.1 (#53)
- Step 5 Preview: 62.8 (#71)

| Benchmark | Kimi K2.5 | Step 5 Preview |
|---|---|---|
| LMArena Text | 1445 | 1442 |
| LMArena Creative Writing | 1423 | 1410 |
| LMArena Multi-Turn | 1444 | 1447 |
| EQ-Bench Creative Writing | 1579 | — |

## FAQ

### Is Kimi K2.5 better than Step 5 Preview?

Kimi K2.5 and Step 5 Preview score almost the same on the Noometry Index (48.1 vs 47.9), so choose on price, context window or the category you care about most.

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

Kimi K2.5 is cheaper. It lists at $0.45 per million input tokens and $2.25 per million output tokens; Step 5 Preview lists at $1 and $2.70.

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

Step 5 Preview scores higher on coding benchmarks: 51.8 versus 48.8 in the Noometry coding category.

### Which has the bigger context window?

Step 5 Preview does, with 1.02M tokens against 262K.

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

17 benchmarks have published results for both models. Kimi K2.5 has 51 scored results on Noometry and Step 5 Preview has 18.