Is GPT-5.1-Instant or GPT-5.1 cheaper?

GPT-5.1-Instant and GPT-5.1 have comparable output pricing.

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

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

GPT-5.1-Instant vs GPT-5.1

Both have similar output pricing, while GPT-5.1 offers a larger context window. Choose GPT-5.1-Instant or GPT-5.1 based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	GPT-5.1-Instant	GPT-5.1
Provider	Poe	Poe
Input / 1M tokens	$1.10	$1.10
Output / 1M tokens	$9.00	$9.00
Context window	128K	400K
Parameters	—	—
Open weights	No	No
Released	Nov 2025	Nov 2025

GPT-5.1-Instant 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.