Is GPT-5.5-Pro or GPT-5.1-Codex cheaper?

GPT-5.1-Codex is cheaper on output tokens ($9.00 vs $163.64 per 1M).

Which has the larger context window, GPT-5.5-Pro or GPT-5.1-Codex?

Both models offer a similar context window.

GPT-5.5-Pro vs GPT-5.1-Codex

GPT-5.1-Codex is cheaper on output tokens. Choose GPT-5.5-Pro or GPT-5.1-Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	GPT-5.5-Pro	GPT-5.1-Codex
Provider	Poe	Poe
Input / 1M tokens	$27.27	$1.10
Output / 1M tokens	$163.64	$9.00
Context window	400K	400K
Parameters	—	—
Open weights	No	No
Released	Apr 2026	Nov 2025

GPT-5.5-Pro details →GPT-5.1-Codex details →

FAQ

Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.