Data points: 109
Model compare
The readout for GPT-5.1 Codex and GPT-5.4, before the detailed comparison sheet.
Weighted outcome: GPT-5.4. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
Decision read
GPT-5.4
GPT-5.4 has the higher weighted result; Model A / B score 0 to 100.
Evidence depth
109 data points
Includes 21 benchmark rows, 1 audit samples, and 8 provider examples.
Selection signal
Start with GPT-5.4
The charts below split 30 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 Codex and GPT-5.4: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | GPT-5.1 Codex | GPT-5.4 |
|---|---|---|
| Overall leader | Contender | Leading |
| Weighted overall score | 0.0 pts | 100.0 pts |
| Benchmark category leads | 0 categories | 6 categories |
| Operational advantages | No data | Cheapest input price, Free providers, Provider coverage |
| Context window | 400K tokens | 1.1M tokens |
| Max output | 128K tokens | 128K tokens |
| Modalities | Input TextImage 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 Codex | GPT-5.4 |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Released | Nov 2025 | Mar 2026 |
| Parameters | No data | No data |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | No data | No data |
| OpenRouter ID | openai/gpt-5.1-codex | openai/gpt-5.4 |
| References | No data | No data |
This report only uses LMSpeed data for GPT-5.1 Codex and GPT-5.4: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
GPT-5.1 Codex
GPT-5.1 Codex does not clearly lead in the benchmark or operational dimensions shared by both models.
GPT-5.4
GPT-5.4 is stronger in benchmark categories (Agents, Coding, Reasoning, Knowledge, Math) and operational dimensions (Cheapest input price, Free providers, Provider coverage).
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 Codex
52.4
Avg. score
GPT-5.4
57.4
GPT-5.4 leads by 6.4
GPT-5.4 leads by 12.3
GPT-5.4 leads by 0.5
GPT-5.4 leads by 9.0
GPT-5.4 leads by 3.8
No data
GPT-5.4
GPT-5.4 leads by 1.4
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.1 Codex
winner$1.25/M
Rank #107/162 · confidence 4
GPT-5.4
$2.50/M
Rank #131/162 · confidence 4
GPT-5.1 Codex
winner$3.44/M
Rank #117/162 · confidence 4
GPT-5.4
$5.63/M
Rank #135/162 · confidence 4
GPT-5.1 Codex
winner$10.00/M
Rank #120/162 · confidence 4
GPT-5.4
$15.00/M
Rank #136/162 · confidence 4
GPT-5.1 Codex
67.3
Rank #31/89 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner74.0
Rank #6/89 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
5.7
Rank #30/73 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner23.4
Rank #7/73 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
winner86.0%
Rank #41/188 · confidence 4
GPT-5.4
74.8%
Rank #96/188 · confidence 4
GPT-5.1 Codex
winner23.4%
Rank #47/187 · confidence 4
GPT-5.4
10.6%
Rank #91/187 · confidence 4
GPT-5.1 Codex
13.1
Rank #28/33 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner67.4
Rank #3/33 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
40.2
Rank #56/96 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner56.6
Rank #4/96 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
40.2%
Rank #68/185 · confidence 4
GPT-5.4
winner47.1%
Rank #24/185 · confidence 4
GPT-5.1 Codex
23.4
Rank #45/96 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner41.6
Rank #8/96 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
39.2
Rank #23/90 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner50.0
Rank #9/90 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
34.7
Rank #46/99 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner51.4
Rank #10/99 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
86.0
Rank #40/96 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner92.0
Rank #11/96 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
74.4
Rank #47/90 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner88.6
Rank #18/90 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
72.5
Rank #36/57 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner78.4
Rank #16/57 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
1191.0
Rank #47/66 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner1250.0
Rank #31/66 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
70.0
Rank #39/86 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner73.9
Rank #24/86 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
49.7
Rank #24/50 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner64.9
Rank #4/50 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
26.2
Rank #11/20 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner38.9
Rank #4/20 · confidence 3 · eval date 2026-03-05
GPT-5.1 Codex
83.0
Rank #50/84 · confidence 1 · eval date 2025-10-15
GPT-5.4
winner87.1
Rank #37/84 · confidence 3 · eval date 2026-03-05
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.1 Codex | GPT-5.4 |
|---|---|---|
Winner: GPT-5.4 | GPT-5.1 Codex gpt-5.1-codex No audit yet | GPT-5.4 gpt-5.4 Audit score 93 1008486100 |
Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.
| Provider | GPT-5.1 Codex | GPT-5.4 |
|---|---|---|
100 tests | GPT-5.1 Codex speed / latency N/A / N/A input / output No data | GPT-5.4 speed / latency 57 tok/s / 3556ms input / output No data |
50 tests | GPT-5.1 Codex speed / latency N/A / N/A input / output No data | GPT-5.4 speed / latency 50 tok/s / 7305ms input / output No data |
20 tests | GPT-5.1 Codex speed / latency N/A / N/A input / output No data | GPT-5.4 speed / latency 51 tok/s / 4032ms input / output No data |
20 tests | GPT-5.1 Codex speed / latency N/A / N/A input / output No data | GPT-5.4 speed / latency 34 tok/s / 1748ms input / output No data |
20 tests | GPT-5.1 Codex speed / latency N/A / N/A input / output No data | GPT-5.4 speed / latency 49 tok/s / 5435ms input / output No data |
GPT-5.1 Codex gpt-5.1-codex speed / latency No data input / output $0/request | GPT-5.4 gpt-5.4 speed / latency No data input / output $0/request | |
GPT-5.1 Codex gpt-5.1-codex speed / latency No data input / output $0.0041/request | GPT-5.4 gpt-5.4 speed / latency No data input / output $2.57/M | |
GPT-5.1 Codex gpt-5.1-codex speed / latency No data input / output $0.0068/request | GPT-5.4 gpt-5.4-openai-compact speed / latency No data input / output $4.11/M |
Weighted outcome: GPT-5.4. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
Output
| Features | Text inputImage inputText outputTool callingStructured outputsJSON modeReasoning | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning |
|---|
