Gemini 2.5 Flash vs Grok 4.1 Fast
A direct API-pricing comparison between Gemini 2.5 Flash and Grok 4.1 Fast. 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, Grok 4.1 Fast is the cheaper choice at $0.0015 per call — 2.7× less than Gemini 2.5 Flash at $0.0040.
| Gemini 2.5 FlashGoogle | Grok 4.1 FastxAI | |
|---|---|---|
| Input / 1M tokens | $0.300 | $0.200 |
| Output / 1M tokens | $2.50 | $0.500 |
| Cached input / 1M | $0.075 | — |
| Context window | 1M | 256K |
| Provider | xAI |
Green = cheaper on that line. Prices are estimates from public pricing pages; verify against Google and xAI before relying on them.
Which is cheaper, Gemini 2.5 Flash or Grok 4.1 Fast?
On output tokens — usually the dominant cost — Gemini 2.5 Flash charges $2.50 per million versus $0.500 for Grok 4.1 Fast. 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.