Is Anthropic: Claude Sonnet 4.5 or OpenAI: GPT-5 Pro cheaper?

Anthropic: Claude Sonnet 4.5 is cheaper on output tokens ($15.00 vs $120.00 per 1M).

Which has the larger context window, Anthropic: Claude Sonnet 4.5 or OpenAI: GPT-5 Pro?

Anthropic: Claude Sonnet 4.5 has the larger context window (1M tokens).

Anthropic: Claude Sonnet 4.5 vs OpenAI: GPT-5 Pro

Anthropic: Claude Sonnet 4.5 is cheaper on output tokens, while Anthropic: Claude Sonnet 4.5 offers a larger context window. Choose Anthropic: Claude Sonnet 4.5 or OpenAI: GPT-5 Pro based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	Anthropic: Claude Sonnet 4.5	OpenAI: GPT-5 Pro
Provider	Kilo Gateway	Kilo Gateway
Input / 1M tokens	$3.00	$15.00
Output / 1M tokens	$15.00	$120.00
Context window	1M	400K
Parameters	—	—
Open weights	No	No
Released	Sep 2025	Oct 2025

Anthropic: Claude Sonnet 4.5 details →OpenAI: GPT-5 Pro details →

FAQ

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