Is OpenAI: o3 or Anthropic: Claude Opus 4.5 cheaper?

OpenAI: o3 is cheaper on output tokens ($8.00 vs $25.00 per 1M).

Which has the larger context window, OpenAI: o3 or Anthropic: Claude Opus 4.5?

Both models offer a similar context window.

OpenAI: o3 vs Anthropic: Claude Opus 4.5

OpenAI: o3 is cheaper on output tokens. Choose OpenAI: o3 or Anthropic: Claude Opus 4.5 based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	OpenAI: o3	Anthropic: Claude Opus 4.5
Provider	Kilo Gateway	Kilo Gateway
Input / 1M tokens	$2.00	$5.00
Output / 1M tokens	$8.00	$25.00
Context window	200K	200K
Parameters	—	—
Open weights	No	No
Released	Apr 2025	Nov 2025

OpenAI: o3 details →Anthropic: Claude Opus 4.5 details →

FAQ

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