GPT-5.1 Codex
OpenAI · model · context window 400,000 tokens.
Pricing (per 1M tokens)
Specifications
Intelligence & value
MeasuredWorth it? GPT-5.1 Codex is on the price/quality frontier — nothing we track matches its overall Arena score for less. If you can accept a small quality drop, the downgrade calculator finds cheaper options.
Intelligence scores are community Arena ratings from LMArena / arena.ai, used under CC BY 4.0. Snapshot last refreshed 18 September 2026. Scores are a relative signal, not an absolute measure of capability. A Measured score was voted on directly; an Estimated score is inherited from an identical base model (a regional/creator-prefixed hosting duplicate). See our methodology.
Where else you can run GPT-5.1 Codex
The same model is resold by 19 providers we track. The typical one charges 1.2× what the cheapest does — $3.44 against $2.93 per 1M tokens, blended 3:1. Routing the same workload to a different host is often a bigger saving than switching model.
| Provider | Input / 1M | Output / 1M | Blended |
|---|---|---|---|
| Opencode | $1.07 | $8.50 | $2.93 |
| Poe | $1.10 | $9.00 | $3.08 |
| Jiekou | $1.13 | $9.00 | $3.09 |
| Abacus | $1.25 | $10.00 | $3.44 |
| Aihubmix | $1.25 | $10.00 | $3.44 |
| Azure | $1.25 | $10.00 | $3.44 |
| Azure Cognitive Services | $1.25 | $10.00 | $3.44 |
| Edenai | $1.25 | $10.00 | $3.44 |
| Helicone | $1.25 | $10.00 | $3.44 |
| Impossibl | $1.25 | $10.00 | $3.44 |
Showing the 10 cheapest of 19. The full list for every model is in the open endpoint dataset.
Third-party listings via models.dev, not rates we verify with each host the way we do first-party pricing. Treat them as a shortlist to check, not a quote — and confirm quantisation, context limits and rate limits before switching, since a cheaper host is not always serving the same thing.
Estimate cost with GPT-5.1 Codex
GPT-5.1 Codex is pre-selected below. Enter your token counts and volume to see the cost per request, per day and per month — then switch models to compare.
Results update automatically as you type.
- Input cost
- $0.00125
- Output cost
- $0.00500
- Per request
- $0.00625
- Per day
- $6.25
- Per month
- $187.50
Source: auto-discovery (models.dev). Prices are re-checked daily against the provider’s official pricing; this rate was last changed on 19 July 2026. A recent date here just means the price is still current, not that it moved.