Compare models
GPT-5.1-Codex-Max
A version of GPT-5.1-codex optimized for long running tasks.
Reasoning
Speed
Input
Output
Reasoning tokens
Pricing
Text tokens
Input / 1M tokens
$1.25
Cached input / 1M tokens
$0.125
Output / 1M tokens
$10.00
Cache writes / 1M tokens
-
Context
Window
400,000
Max Output Tokens
128,000
Knowledge Cutoff
Sep 30, 2024
Endpoints
v1/chat/completions
v1/responses
v1/batch
Supported Features
Streaming
Function calling
Structured outputs
Image input
Rate Limits
TPM
Free
-
Tier 1
500,000
Tier 2
1,000,000
Tier 3
2,000,000
Tier 4
4,000,000
Tier 5
40,000,000
GPT-6 Astra
Our most capable model, built for the hardest end-to-end work
Reasoning
Speed
Input
Output
Reasoning tokens
Pricing
Text tokens
Input / 1M tokens
$10.00
Cached input / 1M tokens
$1.00
Output / 1M tokens
$50.00
Cache writes / 1M tokens
$12.50
Context
Window
1,050,000
Max Output Tokens
128,000
Knowledge Cutoff
Apr 30, 2026
Endpoints
v1/chat/completions
v1/responses
v1/batch
Supported Features
Streaming
Function calling
Structured outputs
Image input
Rate Limits
TPM
Free
-
Tier 1
500,000
Tier 2
1,000,000
Tier 3
2,000,000
Tier 4
4,000,000
Tier 5
40,000,000