# GPT-5.4 vs Kimi K2 (Jul 2025)

> GPT-5.4 is the stronger model overall, scoring 59.5 to 40.9 on the Noometry Index. Kimi K2 (Jul 2025) costs 5.6× less per token, which makes it the better buy when GPT-5.4's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-4-vs-kimi-k2
- Last updated: 2026-10-10
- Shared benchmarks: 30

## Summary

- They share 30 benchmarks with published results for both. GPT-5.4 scores higher in 9 categories and Kimi K2 (Jul 2025) in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.4 leads 61.7 to 22.7.
- The biggest single-benchmark swing is Terminal-Bench: 81.8% for GPT-5.4 and 35.7% for Kimi K2 (Jul 2025).
- Kimi K2 (Jul 2025) is cheaper at $0.57 / $2.30 per million input/output tokens, against $2.50 / $15 for GPT-5.4.
- GPT-5.4 accepts more context: 1.05M tokens versus 262K.
- Kimi K2 (Jul 2025) has downloadable open weights; the other is API-only.

## Snapshot

| | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| Provider | OpenAI | Moonshot AI |
| Noometry Index | 59.5 | 40.9 |
| Rank | 14 | 134 |
| Context | 1.05M | 262K |
| Input $/M | $2.50 | $0.57 |
| Output $/M | $15 | $2.30 |
| Weights | Proprietary | Open |

## Coding

- GPT-5.4: 52.8 (#28)
- Kimi K2 (Jul 2025): 43.1 (#83)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| GSO | 31.4% | 4.9% |
| WeirdML | 77.7% | 42.8% |
| LMArena Coding | 1497 | 1399 |
| ALE-Bench | 1,607 | 597.5 |
| SWE-bench Verified | 76.9% | — |
| DeepSWE | 51.8% | — |
| SWE-bench Verified (bash only) | — | 63.4% |
| Aider Polyglot | — | 59.1% |
| LMArena WebDev | 1465 | — |
| SciCode | 56.6% | — |
| MirrorCode | 15.6% | — |
| AlgoTune | 1.85 | — |

## Agentic & Tool Use

- GPT-5.4: 46.5 (#12)
- Kimi K2 (Jul 2025): 32.2 (#59)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| Terminal-Bench | 81.8% | 35.7% |
| METR Time Horizons | 74.3% | 59.2% |
| APEX-Agents | 52.4% | — |
| Berkeley Function Calling Leaderboard | — | 59.1% |
| τ²-bench Banking | 39.4% | — |
| DeepResearch Bench | 35.1% | — |
| PostTrainBench | 19% | — |
| GBAEval | 45.1% | — |
| LMArena Search | 1197 | — |
| Vending-Bench 2 | 6,144 | — |

## Reasoning

- GPT-5.4: 61.7 (#17)
- Kimi K2 (Jul 2025): 22.7 (#173)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| Kagi LLM Benchmark | 63.8% | 64.4% |
| LMArena Hard Prompts | 1485 | 1384 |
| Epoch Capabilities Index | 156.92 | 146.02 |
| ForecastBench | 59.5 | 60.2 |
| ARC-AGI-2 | 74% | — |
| SimpleBench | — | 26.3% |
| NYT Connections (extended) | 91.3% | — |
| ARC-AGI-1 | 93.7% | — |
| CritPt | 23.4% | — |
| Chess Puzzles | 44% | — |
| EnigmaEval | 16% | — |
| Thematic Generalization | 80% | — |
| EBR-Bench | 25.4% | — |
| Mystery Game Puzzles | 37% | — |
| DTBench | 94.4% | — |
| LMCA | 52% | — |

## Math

- GPT-5.4: 73.3 (#14)
- Kimi K2 (Jul 2025): 40.1 (#81)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| LMArena Math | 1488 | 1396 |
| FrontierMath (Feb 2025 set) | 47.6% | 21.4% |
| FrontierMath Tier 4 (v1) | 27.1% | 0% |
| FrontierMath (Tiers 1-3) | 78.6% | — |
| FrontierMath Tier 4 | 49% | — |
| MathArena Final-Answer Competitions | 83.1% | — |
| OTIS Mock AIME 2024-2025 | 97.8% | — |
| ProofBench | 56% | — |
| Omni-MATH | — | 65.4% |

## Knowledge

- GPT-5.4: 65.3 (#13)
- Kimi K2 (Jul 2025): 36.9 (#153)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| Vectara Hallucination Rate | 7% | 17.9% |
| LMArena Expert | 1507 | 1363 |
| GPQA Diamond | 93.3% | — |
| Humanity's Last Exam | 36.2% | — |
| SimpleQA Verified | 45.1% | — |
| MMLU-Pro | — | 81.9% |
| Confabulations | — | 20.4% |
| GPQA (HELM) | — | 65.3% |

## Multimodal

- GPT-5.4: 43.8 (#19)
- Kimi K2 (Jul 2025): —

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| LMArena Vision | 1302 | — |
| Blueprint-Bench 2 | 27.1% | — |
| Furniture Assembly | 37.5% | — |
| LMArena Document | 1471 | — |

## Multilingual

- GPT-5.4: 56.4 (#22)
- Kimi K2 (Jul 2025): 49.8 (#125)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| LMArena Non-English | 1465 | 1372 |
| LMArena Chinese | 1520 | 1416 |
| LMArena French | 1493 | 1379 |
| LMArena German | 1472 | 1386 |
| LMArena Japanese | 1484 | 1349 |
| LMArena Korean | 1449 | 1324 |
| LMArena Russian | 1480 | 1384 |
| LMArena Spanish | 1453 | 1383 |

## Instruction Following

- GPT-5.4: 77.3 (#25)
- Kimi K2 (Jul 2025): 71.3 (#151)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| LMArena Instruction Following | 1469 | 1347 |
| IFEval | — | 85% |

## Long Context

- GPT-5.4: 50.3 (#8)
- Kimi K2 (Jul 2025): 41.2 (#140)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| CL-bench | 27.9% | 17.6% |
| LMArena Longer Query | 1474 | 1353 |
| Fiction.LiveBench | — | 66.7% |
| CL-bench Life | 21.7% | — |

## Writing & Preference

- GPT-5.4: 72.1 (#18)
- Kimi K2 (Jul 2025): 62.5 (#76)

| Benchmark | GPT-5.4 | Kimi K2 (Jul 2025) |
|---|---|---|
| LMArena Text | 1469 | 1380 |
| LMArena Creative Writing | 1439 | 1349 |
| EQ-Bench Creative Writing | 1840 | 1666 |
| LMArena Multi-Turn | 1482 | 1371 |
| Short-Story Creative Writing | — | 85.6% |
| WildBench | — | 86.2% |
| EQ-Bench 4 | 1272 | — |

## FAQ

### Is GPT-5.4 better than Kimi K2 (Jul 2025)?

GPT-5.4 is the stronger model overall, scoring 59.5 to 40.9 on the Noometry Index. Kimi K2 (Jul 2025) costs 5.6× less per token, which makes it the better buy when GPT-5.4's lead doesn't matter for your workload.

### Which is cheaper, GPT-5.4 or Kimi K2 (Jul 2025)?

Kimi K2 (Jul 2025) is cheaper. It lists at $0.57 per million input tokens and $2.30 per million output tokens; GPT-5.4 lists at $2.50 and $15.

### Is GPT-5.4 or Kimi K2 (Jul 2025) better for coding?

GPT-5.4 scores higher on coding benchmarks: 52.8 versus 43.1 in the Noometry coding category.

### Which has the bigger context window?

GPT-5.4 does, with 1.05M tokens against 262K.

### How many benchmarks do GPT-5.4 and Kimi K2 (Jul 2025) share?

30 benchmarks have published results for both models. GPT-5.4 has 68 scored results on Noometry and Kimi K2 (Jul 2025) has 42.