GPT-5.1 pricing & specs
OpenAI · released 2025-11-13 · ● verified 2026-10-11
input / 1M$1.25
output / 1M$10.00
context400K
max output128K
// price history ($/1M tokens)
// cheaper or similar alternatives
| model | in | out | ctx | vs GPT-5.1 |
|---|---|---|---|---|
| Qwen3.7 Flash | $0.03 | $0.13 | 1M | −98.4% |
| Qwen3.5 9B | $0.10 | $0.15 | 262.1K | −96.7% |
| Gemma 4 26B A4B IT | $0.07 | $0.34 | 262.1K | −96% |
| GPT-5 Nano | $0.05 | $0.40 | 400K | −96% |
| Qwen3.5 Flash | $0.10 | $0.40 | 1M | −94.9% |
// faq
How much does GPT-5.1 cost?
GPT-5.1 costs $1.25 per million input tokens and $10.00 per million output tokens. At 50M input and 10M output tokens per month that is about $163.
What is the context window of GPT-5.1?
400K tokens, with up to 128K output tokens per request.
Does GPT-5.1 support prompt caching?
Yes. Cached input tokens cost $0.125 per million.
What are cheaper alternatives to GPT-5.1?
Qwen3.7 Flash ($0.03 in / $0.13 out), Qwen3.5 9B ($0.10 in / $0.15 out), Gemma 4 26B A4B IT ($0.07 in / $0.34 out) offer the same input types and capabilities for less.
// spec sheet
- input / 1M
- $1.25
- output / 1M
- $10.00
- cache read / 1M
- $0.125
- blended (3:1)
- $3.4375
- context
- 400K
- max output
- 128K
- input types
- text · image
- reasoning
- yes
- tool calling
- yes
- structured output
- yes
- open weights
- no
- knowledge cutoff
- 2024-09-30
- price source
- OpenAI
// cost calculator
| model | in $/1M | out $/1M | = monthly |
|---|---|---|---|
| Qwen3.7 Flash | $0.03 | $0.13 | $2.80 |
| Qwen3.5 9B | $0.10 | $0.15 | $6.50 |
| Gemma 4 26B A4B IT | $0.07 | $0.34 | $6.90 |
| GPT-5.1 | $1.25 | $10.00 | $163 |
Base-tier list prices. Long-context tiers, caching and batch discounts are not included.