Data points: 108
Model compare
The readout for GPT-5.1 and Kimi K2, before the detailed comparison sheet.
Weighted outcome: GPT-5.1. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
Decision read
GPT-5.1
GPT-5.1 has the higher weighted result; Model A / B score 96 to 4.
Evidence depth
108 data points
Includes 21 benchmark rows, 0 audit samples, and 6 provider examples.
Selection signal
Start with GPT-5.1
The charts below split 27 high-signal samples across speed, scores, and audit health.
Switch either side of this report to compare another model with the same LMSpeed data pipeline.
Select a different model to open a new comparison URL.
This report only uses LMSpeed data for GPT-5.1 and Kimi K2: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | GPT-5.1 | Kimi K2 |
|---|---|---|
| Overall leader | Leading | Contender |
| Weighted overall score | 96.0 pts | 4.0 pts |
| Benchmark category leads | 6 categories | 0 categories |
| Operational advantages | Cheapest input price, Average speed, Free providers, Provider coverage | First-token latency |
| Context window | 400K tokens | 131.1K tokens |
| Max output | 128K tokens | 100.4K tokens |
| Modalities | Input ImageTextFile Output Text |
The overall result weights benchmark capability categories at 80% and price, API speed/latency, and availability at 20%. Recent test volume does not affect the winner, and missing benchmark categories are excluded.
| Model compare | GPT-5.1 | Kimi K2 |
|---|---|---|
| Developer | OpenAI | MoonshotAI |
| Released | Nov 2025 | Sep 2025 |
| Parameters | No data | No data |
| Tokenizer | GPT | Other |
| Knowledge cutoff | No data | 2024-12-31 |
| OpenRouter ID | openai/gpt-5.1 | moonshotai/kimi-k2 |
| References | No data | No data |
This report only uses LMSpeed data for GPT-5.1 and Kimi K2: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
GPT-5.1
GPT-5.1 is stronger in benchmark categories (Agents, Coding, Reasoning, Knowledge, Math) and operational dimensions (Cheapest input price, Average speed, Free providers, Provider coverage).
Kimi K2
Kimi K2 has these operational advantages: First-token latency.
Third-party benchmark profile synced into LMSpeed; only metrics available for both models are shown.
Compare benchmark category scores on a 0-100 scale. Select a category to inspect the gap.
Avg. score
GPT-5.1
52
Avg. score
Kimi K2
47.8
GPT-5.1 leads by 2.4
GPT-5.1 leads by 0.6
GPT-5.1 leads by 3.5
GPT-5.1 leads by 8.4
GPT-5.1 leads by 0.2
No data
No data
GPT-5.1 leads by 10.0
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.1
winner56.0
Rank #41/84 · confidence 1 · eval date 2025-11-13
Kimi K2
51.0
Rank #56/84 · confidence 1 · eval date 2025-07-01
GPT-5.1
$10.00/M
Rank #120/162 · confidence 4
Kimi K2
winner$2.30/M
Rank #72/162 · confidence 4
GPT-5.1
$3.44/M
Rank #117/162 · confidence 4
Kimi K2
winner$1.00/M
Rank #77/162 · confidence 4
GPT-5.1
$1.25/M
Rank #107/162 · confidence 4
Kimi K2
winner$0.570/M
Rank #79/162 · confidence 4
GPT-5.1
winner75.0
Rank #3/89 · confidence 1 · eval date 2025-11-13
Kimi K2
51.0
Rank #66/89 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner87.0%
Rank #12/125 · confidence 4
Kimi K2
82.4%
Rank #44/125 · confidence 4
GPT-5.1
winner87.3%
Rank #33/188 · confidence 4
Kimi K2
76.6%
Rank #90/188 · confidence 4
GPT-5.1
winner26.5%
Rank #40/187 · confidence 4
Kimi K2
7.0%
Rank #115/187 · confidence 4
GPT-5.1
winner86.8%
Rank #4/115 · confidence 4
Kimi K2
55.6%
Rank #50/115 · confidence 4
GPT-5.1
winner43.3%
Rank #42/185 · confidence 4
Kimi K2
34.5%
Rank #114/185 · confidence 4
GPT-5.1
winner43.3
Rank #45/96 · confidence 1 · eval date 2025-11-13
Kimi K2
34.5
Rank #78/96 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner31.0
Rank #19/47 · confidence 1 · eval date 2025-11-13
Kimi K2
21.4
Rank #27/47 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner49.9
Rank #30/56 · confidence 1 · eval date 2025-11-13
Kimi K2
39.3
Rank #38/56 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner37.6
Rank #31/90 · confidence 1 · eval date 2025-11-13
Kimi K2
26.8
Rank #49/90 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner87.3
Rank #36/96 · confidence 1 · eval date 2025-11-13
Kimi K2
76.6
Rank #66/96 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner26.5
Rank #39/96 · confidence 1 · eval date 2025-11-13
Kimi K2
7.0
Rank #74/96 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner36.9
Rank #42/99 · confidence 1 · eval date 2025-11-13
Kimi K2
19.4
Rank #74/99 · confidence 1 · eval date 2025-07-01
GPT-5.1
51.3
Rank #65/90 · confidence 1 · eval date 2025-11-13
Kimi K2
winner74.2
Rank #49/90 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner1217.0
Rank #39/66 · confidence 1 · eval date 2025-11-13
Kimi K2
1080.0
Rank #57/66 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner72.9
Rank #30/86 · confidence 1 · eval date 2025-11-13
Kimi K2
41.5
Rank #67/86 · confidence 1 · eval date 2025-07-01
GPT-5.1
winner81.9
Rank #52/84 · confidence 1 · eval date 2025-11-13
Kimi K2
61.1
Rank #63/84 · confidence 1 · eval date 2025-07-01
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.1 | Kimi K2 |
|---|---|---|
| No completed audits are available from shared providers yet. | ||
Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.
| Provider | GPT-5.1 | Kimi K2 |
|---|---|---|
10 tests | GPT-5.1 speed / latency 179 tok/s / 6622ms input / output No data | Kimi K2 speed / latency 50 tok/s / 1054ms input / output No data |
5 tests | GPT-5.1 speed / latency 96 tok/s / 1862ms input / output No data | Kimi K2 speed / latency N/A / N/A input / output No data |
0 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | Kimi K2 speed / latency N/A / N/A input / output No data |
0 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | Kimi K2 speed / latency N/A / N/A input / output No data |
0 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | Kimi K2 speed / latency N/A / N/A input / output No data |
GPT-5.1 gpt-5.1 speed / latency No data input / output $0/request | Kimi K2 Kimi-K2-0905 speed / latency No data input / output $0/request |
Weighted outcome: GPT-5.1. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
Input
Output
| Features | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning | Text inputText outputTool calling |
|---|
