Is GPT OSS 120B or GPT-5.1 cheaper?

GPT OSS 120B is cheaper on output tokens ($0.75 vs $9.00 per 1M).

Which has the larger context window, GPT OSS 120B or GPT-5.1?

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

GPT OSS 120B vs GPT-5.1

GPT OSS 120B is cheaper on output tokens, while GPT-5.1 offers a larger context window. Choose GPT OSS 120B or GPT-5.1 based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	GPT OSS 120B	GPT-5.1
Provider	Cerebras	Poe
Input / 1M tokens	$0.35	$1.10
Output / 1M tokens	$0.75	$9.00
Context window	131K	400K
Parameters	117B	—
Open weights	Yes	No
Released	Aug 2025	Nov 2025

GPT OSS 120B 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.