GPT-5.5 vs Gemini 2.5 Flash

Q: Which is cheaper, GPT-5.5 or Gemini 2.5 Flash?

Gemini 2.5 Flash is cheaper for a typical 5K-in/1K-out request at $0.0040 per call, versus $0.055 for GPT-5.5.

A direct API-pricing comparison between GPT-5.5 and Gemini 2.5 Flash. Below: every cost dimension side by side, then the bottom line for a typical workload.

Bottom line

For a typical 5K-in / 1K-out request, Gemini 2.5 Flash is the cheaper choice at $0.0040 per call — 13.8× less than GPT-5.5 at $0.055.

	GPT-5.5OpenAI	Gemini 2.5 FlashGoogle
Input / 1M tokens	$5.00	$0.300
Output / 1M tokens	$30.00	$2.50
Cached input / 1M	—	$0.075
Context window	400K	1M
Provider	OpenAI	Google

Green = cheaper on that line. Prices are estimates from public pricing pages; verify against OpenAI and Google before relying on them.

Model both in the calculator →

Which is cheaper, GPT-5.5 or Gemini 2.5 Flash?

On output tokens — usually the dominant cost — GPT-5.5 charges $30.00 per million versus $2.50 for Gemini 2.5 Flash. The right pick depends on your input/output ratio and how much you can serve from cache. Use the calculator to model your exact traffic.