Last refreshed 2026-06-15. Next refresh: weekly.
Why use GPT-5.1 Codex Max on OpenRouter?
OpenRouter offers GPT-5.1 Codex Max with pay-as-you-go pricing at $1.25/1M input tokens. OpenRouter is a multi-provider LLM aggregator offering unified API access to 300+ models from all major labs and emerging providers, with automatic failover for reliability.
Compare GPT-5.1 Codex Max across 3 providers to find the best fit for your use caseInput / 1M
$1.25
Output / 1M
$10.00
Cache
read $0.125
Batch
Not sourced
Setup recipe
Docs fallbackInstall
Use the provider REST API or SDKAuth
Create a provider API keyCall
model: openai/gpt-5.1-codex-maxModel ID
openai/gpt-5.1-codex-maxRequest example
Curated snippets for this provider are not sourced yet. Use OpenRouter documentation with model ID
openai/gpt-5.1-codex-max.Gotchas
- Use provider model ID "openai/gpt-5.1-codex-max", not the LLMReference slug "gpt-5.1-codex-max".
Compare GPT-5.1 Codex Max Across Providers
| Provider | Input (per 1M) | Output (per 1M) |
|---|---|---|
| Vercel AI Gateway | $1.25 | $10.00 |
| OpenRouter | $1.25 | $10.00 |
| OpenAI API | $1.25 | $10.00 |
Pricing
| Type | Price (per 1M) |
|---|---|
| Input tokens | $1.25 |
| Output tokens | $10.00 |
Capabilities
VisionMultimodalReasoningJSON / Tool useStructured Outputs
About GPT-5.1 Codex Max
OpenAI's GPT-5.1-Codex-Max is a code-specialized model released November 19, 2025, optimized for agentic coding tasks including project-scale refactors, debugging, and multi-file edits. Uses context compaction to handle long-running tasks beyond a single context window. 30% more token-efficient than previous Codex on SWE-bench. Supports an extra-high reasoning effort option.
Get Started
Model Specs
Released2025-11-19
Knowledge cutoff2024-09