Is Claude-Sonnet-4.5 or GPT-5.1-Codex cheaper?

GPT-5.1-Codex is cheaper on output tokens ($9.00 vs $13.00 per 1M).

Which has the larger context window, Claude-Sonnet-4.5 or GPT-5.1-Codex?

Claude-Sonnet-4.5 has the larger context window (983K tokens).

Claude-Sonnet-4.5 vs GPT-5.1-Codex

GPT-5.1-Codex is cheaper on output tokens, while Claude-Sonnet-4.5 offers a larger context window. Choose Claude-Sonnet-4.5 or GPT-5.1-Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	Claude-Sonnet-4.5	GPT-5.1-Codex
Provider	Poe	Poe
Input / 1M tokens	$2.60	$1.10
Output / 1M tokens	$13.00	$9.00
Context window	983K	400K
Parameters	—	—
Open weights	No	No
Released	Sep 2025	Nov 2025

Claude-Sonnet-4.5 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.