Compare / head-to-head
GPT-5.1-CodexvsGPT-5.1-Codex-Max
GPT-5.1-Codex-Max leads 3 of 3 shared benchmarks. Both list the same combined token price. Both offer a 400K-token context window.
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 3
GPT-5.1-Codex-Max leads
Cheaper per token
Tie
list price, input + output
Larger context
Tie
both 400K tokens
Providers
OpenAI
same provider
GPT-5.1-Codex
OpenAI · released 2025-11-13
textvision
GPT-5.1-Codex-Max
OpenAI · released 2025-11-19
textvision
Quality
Benchmark matrix
3 shared · 1 only GPT-5.1-Codex · 0 only GPT-5.1-Codex-Max| Benchmark | GPT-5.1-Codex | GPT-5.1-Codex-Max | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 3 | ||||
| SWE-bench Verified | 73.7% ↗ | 77.9% ↗ | -4.2 pt | GPT-5.1-Codex-Max |
| SWE-Lancer IC SWE | 66.3% ↗ | 79.9% ↗ | -13.6 pt | GPT-5.1-Codex-Max |
| Terminal-Bench 2.0 | 52.8% ↗ | 58.1% ↗ | -5.3 pt | GPT-5.1-Codex-Max |
| Only GPT-5.1-Codex reports · 1 | ||||
| LMArena WebDev (LMArena) | 1337.1 ↗ | not reported | — | — |
| Only GPT-5.1-Codex-Max reports · 0 | ||||
| GPT-5.1-Codex-Max reports nothing GPT-5.1-Codex does not. | ||||
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5.1-Codex minus GPT-5.1-Codex-Max in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | GPT-5.1-Codex | GPT-5.1-Codex-Max | Edge |
|---|---|---|---|
| Context window | 400K tokens | 400K tokens | Tie |
| Max output | 128K tokens | 128K tokens | Tie |
| Input price / 1M | $1.25 ↗ | $1.25 ↗ | Tie |
| Output price / 1M | $10 ↗ | $10 ↗ | Tie |
| Cached input / 1M | $0.125 ↗ | $0.125 ↗ | Tie |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $11.25 | $11.25 | Tie |
| Modalities | text · vision | text · vision | Tie |
| Released | 2025-11-13 | 2025-11-19 | — |
| Cited benchmark scores | 4 | 3 | — |
Reliability
OpenAI status
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GPT-5.1-Codex vs …
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GPT-5.1-Codex-Max vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
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