Is Aion-2.0 or GPT-5.3 Codex cheaper?

Aion-2.0 is cheaper on output tokens ($1.60 vs $14.00 per 1M).

Which has the larger context window, Aion-2.0 or GPT-5.3 Codex?

GPT-5.3 Codex has the larger context window (400K tokens).

Aion-2.0 vs GPT-5.3 Codex

Aion-2.0 is cheaper on output tokens, while GPT-5.3 Codex offers a larger context window. Choose Aion-2.0 or GPT-5.3 Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	Aion-2.0	GPT-5.3 Codex
Provider	OpenRouter	OpenRouter
Input / 1M tokens	$0.80	$1.75
Output / 1M tokens	$1.60	$14.00
Context window	131K	400K
Parameters	—	—
Open weights	No	No
Released	Feb 2026	Feb 2026

Aion-2.0 details →GPT-5.3 Codex details →

FAQ

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