GPT 5.1

proprietary

Status: Deprecated

Intelligence
Reasoning
Speed
Context
400K
Max output
128K
Input price
$1.07/1M tokens
Output price
$8.5/1M tokens

Capabilities

Reasoning & Interaction
Reasoning
Tool Calling
Output Control
Structured Output
JSON Mode
Infrastructure
Streaming
Batch Processing

Details

Model IDgpt-5.1
Provider OpenCode Zen
Creator OpenAI
Familygpt-5.1
Licenseproprietary
Statusactive
Typechat
Input modalitiestext
Output modalitiestext
Open weightNo
Parameters—
Architecture—
Context window400K tokens
Max input—
Max output128K tokens
Reasoning tokensYes
Knowledge cutoff
Release date
Deprecation date
Sourceofficial

Pricing

Input
$1.07
Output
$8.5
Cache write
—
Cache read
$0.11
Batch in
—
Batch out
—

Family Comparison: gpt-5.1

ModelContextMax outPricing
GPT 5.1 Codex Mini400K128K$0.25$2
GPT 5.1 Codex400K128K$1.07$8.5
GPT 5.1400K128K$1.07$8.5
GPT 5.1 Codex Max400K128K$1.25$10

API

GET/v1/models/opencode/gpt-5.1

GPT 5.1

gpt-5.1

Status: Deprecated

Changes · 3 entries
gpt-5.1updateb301ebeMar 23, 2026, 11:47 PM
modalitiesinput["text"]output["text"]
gpt-5.1update2b100acMar 23, 2026, 05:30 AM
pricingoutput$8.5cached input$0.107
model_typechat
gpt-5.1create7f5c66fMar 21, 2026, 05:16 AM