Input Price
$1.25
per 1M tokens
Output Price
$10
per 1M tokens
Context Window
1,000K
tokens (131.072K max output)
Specifications
Release Date2025-11-12
Category🏆 Flagship
Context Window1,000,000 tokens
Max Output131,072 tokens
Capabilities
textvisionaudiocodereasoning
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Monthly Cost Estimates
| Usage Level | Daily Tokens | Daily | Monthly | Yearly |
|---|---|---|---|---|
| Light~50 requests/day | 100K in / 20K out | $0.33 | $9.75 | $119 |
| Medium~200 requests/day | 500K in / 100K out | $1.63 | $48.75 | $593 |
| Heavy~1K requests/day | 2,000K in / 500K out | $7.50 | $225.00 | $2738 |
| Enterprise~5K requests/day | 10,000K in / 2,000K out | $32.50 | $975.00 | $11863 |
Cost Calculator
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Frequently Asked Questions
How much does GPT-5.1 API cost per million tokens?▼
GPT-5.1 costs $1.25 per million input tokens and $10 per million output tokens as of 2026. These are the standard API rates from OpenAI.
What is the GPT-5.1 context window?▼
GPT-5.1 supports a 1M context window (1,000,000 tokens), which means you can process up to 1M tokens in a single API call.
How much does GPT-5.1 cost per month?▼
At medium usage (~200 requests/day with 500K input and 100K output tokens/day), GPT-5.1 costs approximately $48.75/month. Light usage runs about $9.75/month, and heavy usage (~1K requests/day) around $225.00/month.
Is there a cheaper alternative to GPT-5.1?▼
Yes — o3 by OpenAI is a cheaper option at $2/M input tokens vs $1.25/M for GPT-5.1. Other budget alternatives include models in the efficient tier.
Is GPT-5.1 good for ai agent / agentic workflows?▼
GPT-5.1 is a flagship model with support for text, vision, audio. For ai agent / agentic workflows, it offers 1M context and costs $1.25/M input tokens — a mid-range option for this use case.
GPT-5.1 Comparisons
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