GPT-5.1 Instant is OpenAI's language model with a 128K context window and up to 16K output tokens, starting at $1.25 / 1M input and $10.00 / 1M output. A conversational GPT-5.1 variant with adaptive reasoning that balances speed and depth based on query complexity.
Specifications
Canonical IDopenai-gpt-5-1-instant
TypeLanguage
StatusActive
CreatorOpenAIOpenAI
Providers
Context Window128K tokens
Max Output16K tokens
Input ModalitiesImagePdf
Output ModalitiesText
Reasoning Effortsdefault
Release Date · 6 months ago

Capabilities

Input2/5
Text·
Image
Audio·
Video·
PDF
Output1/5
Text
Image·
Audio·
Video·
Embedding·
Capabilities3/13
Reasoning
Adaptive Reasoning·
Function Calling
Parallel Function Calling·
Structured Outputs·
Native JSON Schema·
Web Search·
URL Context·
Computer Use·
Code Execution·
File Search·
Prompt Caching
Assistant Prefill·

Pricing by Provider

ProviderStandard
Input
$ / 1M
Output
$ / 1M
Cache Read
$ / 1M
Vercel AI Gateway logo
Vercel AI Gateway
openai/gpt-5.1-instant
$1.25$10.00$0.125

Cost Calculator

Preset:

Versions

VersionReleasedContextInput / 1MOutput / 1MStatus
GPT-5.51.1M$5.00$30.00Available
GPT-5.4 Mini1.1M$0.750$4.50Available
GPT-5.4 Nano1.1M$0.200$1.25Available
GPT-5.41.1M$2.50$15.00Available
GPT-5.3 Codex400K$1.75$14.00Available
GPT-5.2 Codex400K$1.75$14.00Available
GPT-5.2410K$1.75$14.00Available
GPT-5.1410K$1.25$10.00Available
GPT-5.1 Codex400K$1.25$10.00Available
GPT-5.1 Codex Mini400K$0.250$2.00Available
GPT-5.1 Instant128K$1.25$10.00Current

Model IDs