GPT-5.1 pricing
GPT-5.1 costs $1.25 per million input tokens and $10 per million output tokens , with cached input at $0.125. Batch requests are discounted 50%.
Price per million tokens
| Input | $1.25 |
| Cached input | $0.125 |
| Output | $10 |
| Context window | not published |
| Batch discount | −50% |
What it costs in practice
Monthly cost for three common workload shapes, with prompt caching applied.
| Workload | Shape | Per request | Per month |
|---|---|---|---|
| Support chatbot | 1.5k in / 400 out, 100k requests/month, 30% cached | $0.00537 | $536.88 |
| RAG / document Q&A | 12k in / 700 out, 50k requests/month, 60% cached | $0.0139 | $695.00 |
| Coding agent | 25k in / 2.5k out, 20k requests/month, 80% cached | $0.0338 | $675.00 |
Model your own workload with caching, batching and tokenizer correction →
Comparable models from other providers
| Model | Provider | Input | Output |
|---|---|---|---|
| Gemini 2.5 Pro | $1.25 | $10 | |
| Grok 4.3 | xAI | $1.25 | $2.5 |
| DeepSeek V4 Pro | DeepSeek | $1.32 | $3.96 |
| Gemini 3.5 Flash | $1.5 | $9 |
All figures verified 2026-08-18 against OpenAI's official pricing documentation . Fields the provider does not publish are shown as “—” rather than estimated.