Model comparison
GPT-5.3 Codex vs o1-pro
GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 31.5 on the Noometry Index.
Last verified . 0 shared benchmarks.
Summary
- GPT-5.3 Codex is cheaper at $1.75 / $14 per million input/output tokens, against $150 / $600 for o1-pro.
- GPT-5.3 Codex accepts more context: 400K tokens versus 200K.
Side by side
| GPT-5.3 Codex | o1-pro | |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Noometry Index | 45.8 | 31.5 |
| Released | 2026-02-05 | 2025-03-19 |
| Weights | Proprietary | Proprietary |
| Context window | 400K | 200K |
| Max output | 128K | 100K |
| Input $ / M tokens | $1.75 | $150 |
| Output $ / M tokens | $14 | $600 |
| Results tracked | 8 | 3 |
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Category by category
Coding Not comparable
GPT-5.3 Codex: 48.6 (#56), o1-pro: —
| Benchmark | GPT-5.3 Codex | o1-pro |
|---|---|---|
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1409 | — |
| WeirdML | 79.3% | — |
| ALE-Bench | 1,655 | — |
Agentic & Tool Use Not comparable
GPT-5.3 Codex: 48.0 (#9), o1-pro: —
| Benchmark | GPT-5.3 Codex | o1-pro |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |
Reasoning Not comparable
GPT-5.3 Codex: —, o1-pro: 20.4 (#239)
| Benchmark | GPT-5.3 Codex | o1-pro |
|---|---|---|
| ARC-AGI-1 | — | 23.3% |
| EnigmaEval | — | 6.1% |
| Epoch Capabilities Index | 156.77 | — |
Knowledge Not comparable
GPT-5.3 Codex: —, o1-pro: 29.7 (#234)
| Benchmark | GPT-5.3 Codex | o1-pro |
|---|---|---|
| Humanity's Last Exam | — | 8.1% |
Frequently asked questions
Is GPT-5.3 Codex better than o1-pro?
GPT-5.3 Codex is the stronger model overall, scoring 45.8 to 31.5 on the Noometry Index.
Which is cheaper, GPT-5.3 Codex or o1-pro?
GPT-5.3 Codex is cheaper. It lists at $1.75 per million input tokens and $14 per million output tokens; o1-pro lists at $150 and $600.
Which has the bigger context window?
GPT-5.3 Codex does, with 400K tokens against 200K.
How many benchmarks do GPT-5.3 Codex and o1-pro share?
0 benchmarks have published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and o1-pro has 3.