Is GPT-5.3 Chat or GPT-5.1-Codex cheaper?

GPT-5.1-Codex is cheaper on output tokens ($10.00 vs $14.00 per 1M).

Which has the larger context window, GPT-5.3 Chat or GPT-5.1-Codex?

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

GPT-5.3 Chat vs GPT-5.1-Codex

GPT-5.1-Codex is cheaper on output tokens, while GPT-5.1-Codex offers a larger context window. Choose GPT-5.3 Chat or GPT-5.1-Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	GPT-5.3 Chat	GPT-5.1-Codex
Provider	ZenMux	ZenMux
Input / 1M tokens	$1.75	$1.25
Output / 1M tokens	$14.00	$10.00
Context window	128K	400K
Parameters	—	—
Open weights	No	No
Released	Mar 2026	Nov 2025

GPT-5.3 Chat 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.