Data points: 79
The readout for GPT-5 and GPT-5.1 Codex, before the detailed comparison sheet.
Decision read
GPT-5
GPT-5 currently has the stronger profile, with verified wins split 3 to 0.
Evidence depth
79 data points
Includes 8 benchmark rows, 0 audit samples, and 10 provider examples.
Selection signal
Start with GPT-5
The charts below split 18 high-signal samples across speed, scores, and audit health.
Model compare GPT-5 vs GPT-5.1 Codexgpt-5-vs-gpt-5-1-codex | Model A GPT-5 | Model B GPT-5.1 Codex |
|---|---|---|
| Overall leader | Leading | Contender |
| Verified metric wins | 3 wins | 0 wins |
| Where it leads | Cheapest input price, Provider coverage, Recent tests | No data |
Third-party benchmark profile synced into LMSpeed; only metrics available for both models are shown.
| Metric | GPT-5 | GPT-5.1 Codex |
|---|---|---|
| MMLU-Pro | 87.1%#7 |
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5 | 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 | GPT-5.1 Codex |
|---|---|---|
20 tests | GPT-5 speed / latency 95 tok/s / 1234ms input / output No data | GPT-5.1 Codex |
This report only uses LMSpeed data for GPT-5 and GPT-5.1 Codex: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Guidance | GPT-5 | GPT-5.1 Codex |
|---|---|---|
| When to choose each model | GPT-5 GPT-5 is stronger when you prioritize Cheapest input price, Provider coverage, Recent tests. | GPT-5.1 Codex GPT-5.1 Codex does not clearly lead on the verified metrics here, so check provider-specific pricing before choosing. |
TL;DR: GPT-5 leads across 79 verifiable data points, including pricing, speed, latency, benchmarks, and provider examples.
Continue from GPT-5 vs GPT-5.1 Codex into nearby model comparisons with enough verified LMSpeed data.
| Model metadata | GPT-5 exposes 128K tokens; notable signals: Text input, Image input, File input, Text output. | GPT-5.1 Codex exposes 400K tokens; notable signals: Text input, Image input, Text output, Tool calling. |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Context window | 128K tokens | 400K tokens |
| Max output | 16.4K tokens | 128K tokens |
| Released | Aug 2025 | Nov 2025 |
| Modalities | Input FileImageText Output Text | Input TextImage Output Text |
| Features | Text inputImage inputFile inputText outputStructured outputsJSON mode | Text inputImage inputText outputTool callingStructured outputsJSON modeReasoning |
| Parameters | No data | No data |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | 2024-09-30 | No data |
| OpenRouter ID | openai/gpt-5-chat | openai/gpt-5.1-codex |
| References | No data | No data |
| LiveCodeBench | 84.6%#11 | 84.9%#10 |
|---|
| Output speed | 109.6 tok/s#44 | 185.7 tok/s#15 |
|---|
| HLE | 26.5%#24 | 23.4%#33 |
|---|
| GPQA | 85.4%#31 | 86.0%#26 |
|---|
| Input price | $1.25/M#30 | $1.25/M#30 |
|---|
| SciCode | 42.9%#31 | 40.2%#46 |
|---|
| Output price | $10.00/M#41 | $10.00/M#41 |
|---|
speed / latency
N/A / N/A
input / output
No data
CatClaw API5 tests | GPT-5 speed / latency 45 tok/s / 3704ms input / output No data | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
|---|
EasyMore5 tests | GPT-5 speed / latency 46 tok/s / 6577ms input / output No data | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
|---|
N1N5 tests | GPT-5 speed / latency 102 tok/s / 948ms input / output No data | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
|---|
Undy API5 tests | GPT-5 speed / latency 131 tok/s / 743ms input / output No data | GPT-5.1 Codex speed / latency N/A / N/A input / output No data |
|---|
GPT-5 gpt-5 speed / latency No data input / output $0/M / $0/M | GPT-5.1 Codex gpt-5.1-codex-openai-compact speed / latency No data input / output $75.00/M / $600.00/M |
GPT-5 gpt-5-all speed / latency No data input / output $0.0068/M / $0.0068/M | GPT-5.1 Codex gpt-5.1-codex-medium speed / latency No data input / output $0.240/M / $1.92/M |
GPT-5 gpt-5-all speed / latency No data input / output $0.0068/M / $0.0068/M | GPT-5.1 Codex gpt-5.1-codex-medium speed / latency No data input / output $0.240/M / $1.92/M |
GPT-5 gpt-5-all-c speed / latency No data input / output $0.0082/M / $0.0082/M | GPT-5.1 Codex gpt-5.1-codex-2025-11-13 speed / latency No data input / output $0.154/M / $1.23/M |
GPT-5 gpt-5 speed / latency No data input / output $0.010/M / $0.010/M | GPT-5.1 Codex gpt-5.1-codex speed / latency No data input / output $0.010/M / $0.010/M |
Rankings are based on community-submitted tests and periodic health probes. Advisory only, not official data.
