LLM API PricesUpdated 2026-09-17 06:21:06 UTC

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GPT 5.1 Codex API price

gpt-5.1-codex

The cheapest GPT 5.1 Codex API is $1.25/M input at OpenRouter (aggregator) - all 2 providers compared below, per 1M tokens.

MidOpenAI400K context2 sellers
Input $1.25 per 1M tokens · OpenRouter (aggregator)
Output $10.00 per 1M tokens · OpenRouter (aggregator)

Where to buy it

Cheapest GPT 5.1 Codex API providers compared - 2 sellers, from $1.25/M.

Cost calculator
ProviderInput $/MOutput $/MCached inYour cost
OpenRouter (aggregator)stale1.25cheapest10.000.130
OrcaRouter (aggregator)1.2510.00-

Against its tier

#26 of 34 mid · cheaper than 24%

Details

Context window
400K400,000 tokens
Developer
OpenAI
Intelligence
23.7est.high
Sellers
2
Cached input
$0.13where the source publishes one
Cheapest at
OpenRouter (aggregator)
Combined
$11.25in + out per 1M
Last checked
2026-09-17

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