Is GLM-5.1 or GPT-5.1-Codex cheaper?

GLM-5.1 is cheaper on output tokens ($3.51 vs $10.00 per 1M).

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

GPT-5.1-Codex has the larger context window (400K tokens).

GLM-5.1 vs GPT-5.1-Codex

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

Spec	GLM-5.1	GPT-5.1-Codex
Provider	ZenMux	ZenMux
Input / 1M tokens	$0.88	$1.25
Output / 1M tokens	$3.51	$10.00
Context window	200K	400K
Parameters	754B	—
Open weights	No	No
Released	Apr 2026	Nov 2025

GLM-5.1 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.