Is GPT-5.1 or GPT OSS 120B cheaper?

GPT OSS 120B is cheaper on output tokens ($0.15 vs $10.00 per 1M).

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

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

GPT-5.1 vs GPT OSS 120B

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

Spec	GPT-5.1	GPT OSS 120B
Provider	OpenRouter	OpenRouter
Input / 1M tokens	$1.25	$0.03
Output / 1M tokens	$10.00	$0.15
Context window	400K	131K
Parameters	—	117B
Open weights	No	Yes
Released	Nov 2025	Aug 2025

GPT-5.1 details →GPT OSS 120B details →

FAQ

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