Is OpenAI: GPT-5.5 Pro or Anthropic: Claude Opus 4.5 cheaper?

Anthropic: Claude Opus 4.5 is cheaper on output tokens ($25.00 vs $180.00 per 1M).

Which has the larger context window, OpenAI: GPT-5.5 Pro or Anthropic: Claude Opus 4.5?

OpenAI: GPT-5.5 Pro has the larger context window (1.1M tokens).

OpenAI: GPT-5.5 Pro vs Anthropic: Claude Opus 4.5

Anthropic: Claude Opus 4.5 is cheaper on output tokens, while OpenAI: GPT-5.5 Pro offers a larger context window. Choose OpenAI: GPT-5.5 Pro 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: GPT-5.5 Pro	Anthropic: Claude Opus 4.5
Provider	Kilo Gateway	Kilo Gateway
Input / 1M tokens	$30.00	$5.00
Output / 1M tokens	$180.00	$25.00
Context window	1.1M	200K
Parameters	—	—
Open weights	No	No
Released	Apr 2026	Nov 2025

OpenAI: GPT-5.5 Pro 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.