Data points: 106
Model compare
The readout for GPT-5.1 and GPT-5.1 Codex, 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 60 to 40.
Evidence depth
106 data points
Includes 22 benchmark rows, 0 audit samples, and 6 provider examples.
Selection signal
Start with GPT-5.1
The charts below split 28 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-5.1 Codex: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | GPT-5.1 | GPT-5.1 Codex |
|---|---|---|
| Overall leader | Leading | Contender |
| Weighted overall score | 60.0 pts | 40.0 pts |
| Benchmark category leads | 3 categories | 3 categories |
| Operational advantages | Cheapest input price, Free providers, Provider coverage | No data |
| 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-5.1 Codex |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Released | Nov 2025 | Nov 2025 |
| Parameters | No data | No data |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | No data | No data |
| OpenRouter ID | openai/gpt-5.1 | openai/gpt-5.1-codex |
| References | No data | No data |
This report only uses LMSpeed data for GPT-5.1 and GPT-5.1 Codex: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
GPT-5.1
GPT-5.1 is stronger in benchmark categories (Knowledge, Math, Instruction following) and operational dimensions (Cheapest input price, Free providers, Provider coverage).
GPT-5.1 Codex
GPT-5.1 Codex leads these benchmark categories: Agents, Coding, Reasoning.
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
GPT-5.1 Codex
52.4
GPT-5.1 Codex leads by 2.0
GPT-5.1 Codex leads by 1.5
GPT-5.1 Codex leads by 3.5
GPT-5.1 leads by 3.0
GPT-5.1 leads by 0.2
No data
No data
GPT-5.1 leads by 1.0
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.1
$1.25/M
Rank #107/162 · confidence 4
GPT-5.1 Codex
$1.25/M
Rank #107/162 · confidence 4
GPT-5.1
$3.44/M
Rank #117/162 · confidence 4
GPT-5.1 Codex
$3.44/M
Rank #117/162 · confidence 4
GPT-5.1
$10.00/M
Rank #120/162 · confidence 4
GPT-5.1 Codex
$10.00/M
Rank #120/162 · confidence 4
GPT-5.1
winner75.0
Rank #3/89 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
67.3
Rank #31/89 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner87.0%
Rank #12/125 · confidence 4
GPT-5.1 Codex
86.0%
Rank #20/125 · confidence 4
GPT-5.1
4.9
Rank #34/73 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
winner5.7
Rank #30/73 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner87.3%
Rank #33/188 · confidence 4
GPT-5.1 Codex
86.0%
Rank #41/188 · confidence 4
GPT-5.1
winner26.5%
Rank #40/187 · confidence 4
GPT-5.1 Codex
23.4%
Rank #47/187 · confidence 4
GPT-5.1
winner86.8%
Rank #4/115 · confidence 4
GPT-5.1 Codex
84.9%
Rank #9/115 · confidence 4
GPT-5.1
winner24.6
Rank #18/33 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
13.1
Rank #28/33 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner43.3%
Rank #42/185 · confidence 4
GPT-5.1 Codex
40.2%
Rank #68/185 · confidence 4
GPT-5.1
winner43.3
Rank #45/96 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
40.2
Rank #56/96 · confidence 1 · eval date 2025-10-15
GPT-5.1
37.6
Rank #31/90 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
winner39.2
Rank #23/90 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner87.3
Rank #36/96 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
86.0
Rank #40/96 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner26.5
Rank #39/96 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
23.4
Rank #45/96 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner36.9
Rank #42/99 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
34.7
Rank #46/99 · confidence 1 · eval date 2025-10-15
GPT-5.1
51.3
Rank #65/90 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
winner74.4
Rank #47/90 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner75.5
Rank #23/57 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
72.5
Rank #36/57 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner1217.0
Rank #39/66 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
1191.0
Rank #47/66 · confidence 1 · eval date 2025-10-15
GPT-5.1
winner72.9
Rank #30/86 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
70.0
Rank #39/86 · confidence 1 · eval date 2025-10-15
GPT-5.1
41.2
Rank #35/50 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
winner49.7
Rank #24/50 · confidence 1 · eval date 2025-10-15
GPT-5.1
81.9
Rank #52/84 · confidence 1 · eval date 2025-11-13
GPT-5.1 Codex
winner83.0
Rank #50/84 · confidence 1 · eval date 2025-10-15
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.1 | GPT-5.1 Codex |
|---|---|---|
| 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-5.1 Codex |
|---|---|---|
10 tests | GPT-5.1 speed / latency 137 tok/s / 3299ms input / output No data | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
5 tests | GPT-5.1 speed / latency 96 tok/s / 1862ms input / output No data | GPT-5.1 Codex 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 | GPT-5.1 Codex 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 | GPT-5.1 Codex 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 | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
GPT-5.1 gpt-5.1 speed / latency No data input / output $0/request | GPT-5.1 Codex gpt-5.1-codex 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 inputText outputTool callingStructured outputsJSON modeReasoning |
|---|
