Data points: 82
Model compare
The readout for GPT-5.4 and GPT-5 Codex, 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 65.3 to 34.7.
Evidence depth
82 data points
Includes 6 benchmark rows, 1 audit samples, and 7 provider examples.
Selection signal
Start with GPT-5.4
The charts below split 14 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-5.4 and GPT-5 Codex: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | GPT-5.4 | GPT-5 Codex |
|---|---|---|
| Overall leader | Leading | Contender |
| Weighted overall score | 65.3 pts | 34.7 pts |
| Benchmark category leads | 2 categories | 1 categories |
| Operational advantages | Cheapest input price, Free providers, Provider coverage | Average speed, First-token latency |
| Context window | 1.1M tokens | 400K tokens |
| Max output | 128K tokens | 128K tokens |
| Modalities | Input TextImageFile 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-5.4 | GPT-5 Codex |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Released | Mar 2026 | Sep 2025 |
| Parameters | No data | No data |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | No data | 2024-09-30 |
| OpenRouter ID | openai/gpt-5.4 | openai/gpt-5-codex |
| References | No data | No data |
This report only uses LMSpeed data for GPT-5.4 and GPT-5 Codex: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
GPT-5.4
GPT-5.4 is stronger in benchmark categories (Coding, Math) and operational dimensions (Cheapest input price, Free providers, Provider coverage).
GPT-5 Codex
GPT-5 Codex is stronger in benchmark categories (Reasoning) and operational dimensions (Average speed, 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-5.4
57.4
Avg. score
GPT-5 Codex
56
GPT-5.4
GPT-5.4 leads by 6.5
GPT-5 Codex leads by 0.3
GPT-5.4
GPT-5.4 leads by 3.2
No data
GPT-5.4
GPT-5.4
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.4
$2.50/M
Rank #131/162 · confidence 4
GPT-5 Codex
winner$1.25/M
Rank #107/162 · confidence 4
GPT-5.4
$5.63/M
Rank #135/162 · confidence 4
GPT-5 Codex
winner$3.44/M
Rank #117/162 · confidence 4
GPT-5.4
$15.00/M
Rank #136/162 · confidence 4
GPT-5 Codex
winner$10.00/M
Rank #120/162 · confidence 4
GPT-5.4
10.6%
Rank #91/187 · confidence 4
GPT-5 Codex
winner25.6%
Rank #43/187 · confidence 4
GPT-5.4
74.8%
Rank #96/188 · confidence 4
GPT-5 Codex
winner83.7%
Rank #56/188 · confidence 4
GPT-5.4
winner47.1%
Rank #24/185 · confidence 4
GPT-5 Codex
40.9%
Rank #59/185 · confidence 4
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.4 | GPT-5 Codex |
|---|---|---|
Winner: GPT-5.4 | GPT-5.4 gpt-5.4 Audit score 93 1008486100 | GPT-5 Codex gpt-5-codex No audit yet |
Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.
| Provider | GPT-5.4 | GPT-5 Codex |
|---|---|---|
50 tests | GPT-5.4 speed / latency 50 tok/s / 7305ms input / output No data | GPT-5 Codex speed / latency N/A / N/A input / output No data |
20 tests | GPT-5.4 speed / latency 51 tok/s / 4032ms input / output No data | GPT-5 Codex speed / latency N/A / N/A input / output No data |
20 tests | GPT-5.4 speed / latency 49 tok/s / 5435ms input / output No data | GPT-5 Codex speed / latency N/A / N/A input / output No data |
15 tests | GPT-5.4 speed / latency 41 tok/s / 6581ms input / output No data | GPT-5 Codex speed / latency N/A / N/A input / output No data |
15 tests | GPT-5.4 speed / latency 41 tok/s / 2439ms input / output No data | GPT-5 Codex speed / latency 204 tok/s / 2223ms input / output No data |
GPT-5.4 gpt-5.4 speed / latency No data input / output $0.240/M/$1.44/M | GPT-5 Codex gpt-5-codex speed / latency No data input / output $0/M | |
GPT-5.4 gpt-5.4-2026-03-05 speed / latency No data input / output $0/request | GPT-5 Codex gpt-5-codex speed / latency No data input / output $0/request |
Weighted outcome: GPT-5.4. 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 inputImage inputText outputTool callingStructured outputsJSON modeReasoning |
|---|
