Is GLM-5.1 or GPT-5.1 cheaper?

GLM-5.1 is cheaper on output tokens ($4.40 vs $8.50 per 1M).

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

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

GLM-5.1 vs GPT-5.1

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

Spec	GLM-5.1	GPT-5.1
Provider	OpenCode Zen	OpenCode Zen
Input / 1M tokens	$1.40	$1.07
Output / 1M tokens	$4.40	$8.50
Context window	205K	400K
Parameters	754B	—
Open weights	Yes	No
Released	Apr 2026	Nov 2025

GLM-5.1 details →GPT-5.1 details →

FAQ

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