Data points: 87
Model compare
The readout for GPT-5.1 and GPT-5 Nano, 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 69.3 to 30.7.
Evidence depth
87 data points
Includes 11 benchmark rows, 0 audit samples, and 6 provider examples.
Selection signal
Start with GPT-5.1
The charts below split 17 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 GPT-5 Nano: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | GPT-5.1 | GPT-5 Nano |
|---|---|---|
| Overall leader | Leading | Contender |
| Weighted overall score | 69.3 pts | 30.7 pts |
| Benchmark category leads | 2 categories | 1 categories |
| Operational advantages | Average speed, First-token latency, Free providers, Provider coverage | Cheapest input price |
| Context window | 400K tokens | 400K tokens |
| Max output | 128K tokens | 128K tokens |
| Modalities | Input ImageTextFile Output Text | Input |
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 | GPT-5 Nano |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Released | Nov 2025 | Aug 2025 |
| Parameters | No data | No data |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | No data | 2024-05-31 |
| OpenRouter ID | openai/gpt-5.1 | openai/gpt-5-nano |
| References | No data | No data |
This report only uses LMSpeed data for GPT-5.1 and GPT-5 Nano: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
GPT-5.1
GPT-5.1 is stronger in benchmark categories (Reasoning, Math) and operational dimensions (Average speed, First-token latency, Free providers, Provider coverage).
GPT-5 Nano
GPT-5 Nano is stronger in benchmark categories (Coding) and operational dimensions (Cheapest input price).
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
52.1
Avg. score
GPT-5 Nano
50.2
GPT-5.1
GPT-5 Nano leads by 2.3
GPT-5.1 leads by 4.7
GPT-5.1
GPT-5.1 leads by 3.1
No data
No data
GPT-5.1
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.1
111.6 tok/s
Rank #60/136 · confidence 4
GPT-5 Nano
winner174.3 tok/s
Rank #30/136 · confidence 4
GPT-5.1
winner35.90 s
Rank #113/136 · confidence 4
GPT-5 Nano
88.73 s
Rank #132/136 · confidence 4
GPT-5.1
winner35.90 s
Rank #128/136 · confidence 4
GPT-5 Nano
88.73 s
Rank #134/136 · confidence 4
GPT-5.1
$1.25/M
Rank #108/162 · confidence 4
GPT-5 Nano
winner$0.050/M
Rank #2/162 · confidence 4
GPT-5.1
$3.44/M
Rank #118/162 · confidence 4
GPT-5 Nano
winner$0.138/M
Rank #6/162 · confidence 4
GPT-5.1
$10.00/M
Rank #121/162 · confidence 4
GPT-5 Nano
winner$0.400/M
Rank #12/162 · confidence 4
GPT-5.1
winner87.0%
Rank #12/125 · confidence 4
GPT-5 Nano
78.0%
Rank #73/125 · confidence 4
GPT-5.1
winner87.3%
Rank #32/187 · confidence 4
GPT-5 Nano
67.6%
Rank #119/187 · confidence 4
GPT-5.1
winner26.5%
Rank #39/186 · confidence 4
GPT-5 Nano
8.2%
Rank #102/186 · confidence 4
GPT-5.1
winner86.8%
Rank #4/115 · confidence 4
GPT-5 Nano
78.9%
Rank #20/115 · confidence 4
GPT-5.1
winner43.3%
Rank #41/184 · confidence 4
GPT-5 Nano
36.6%
Rank #99/184 · confidence 4
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.1 | GPT-5 Nano |
|---|---|---|
| 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 | GPT-5 Nano |
|---|---|---|
10 tests | GPT-5.1 speed / latency 137 tok/s / 3299ms input / output No data | GPT-5 Nano speed / latency N/A / N/A input / output No data |
10 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | GPT-5 Nano speed / latency 102 tok/s / 12165ms input / output No data |
5 tests | GPT-5.1 speed / latency 96 tok/s / 1862ms input / output No data | GPT-5 Nano speed / latency N/A / N/A input / output No data |
5 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | GPT-5 Nano speed / latency 105 tok/s / 6742ms input / output No data |
0 tests | GPT-5.1 speed / latency N/A / N/A input / output No data | GPT-5 Nano speed / latency N/A / N/A input / output No data |
GPT-5.1 gpt-5.1-chat-latest speed / latency No data input / output $0/request | GPT-5 Nano gpt-5-nano 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%.
Output
| Features | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning |
|---|
