GPT-5.1 vs GPT-5.3 Codex
GPT-5.1 is cheaper on output tokens. Choose GPT-5.1 or GPT-5.3 Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | GPT-5.1 | GPT-5.3 Codex |
|---|---|---|
| Provider | OpenRouter | OpenRouter |
| Input / 1M tokens | $1.25 | $1.75 |
| Output / 1M tokens | $10.00 | $14.00 |
| Context window | 400K | 400K |
| Parameters | — | — |
| Open weights | No | No |
| Released | Nov 2025 | Feb 2026 |
FAQ
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.