Grok 4.1 Fast vs Gemini 2.5 Flash
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
|
by xAI
|
by Google
|
|
|---|---|---|
| Overview | ||
| Status | Current budget | Current budget |
| Released | Sep 22, 2025 | Jun 17, 2025 |
| Pricing per million tokens | ||
| Input | $0.200/Mtok | $0.075/Mtok |
| Output | $0.500/Mtok | $0.300/Mtok |
| Blended avg | $0.350/Mtok | $0.188/Mtok |
| Specifications | ||
| Context window | 2M tokens | 1M tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimage
|
textimageaudiovideo
|
| Benchmarks from Vellum LLM Leaderboard | ||
| Avg benchmark score | 57 | 53.7 |
| Perf / dollar | 162.9 | 286.4 |
| GPQA Diamond | 62 | 55 |
| SWE-Bench | 40 | 38 |
| HumanEval | 83 | 82 |
| MATH 500 | 72 | 72 |
| Providers | ||
| Available from |
xAI — $0.200/$0.500/Mtok
|
Google — $0.075/$0.300/Mtok
|
Cost at scale — 1M tokens (50/50 input/output)
| Volume | Grok 4.1 Fast | Gemini 2.5 Flash | Savings |
|---|---|---|---|
| 1M tokens | $0.35 | $0.19 | $0.16 (45.7%) |
| 10M tokens | $3.5 | $1.88 | $1.63 (46.6%) |
| 100M tokens | $35 | $18.75 | $16.25 (46.4%) |
| 1000M tokens | $350 | $187.5 | $162.5 (46.4%) |
Summary
Grok 4.1 Fast by xAI costs $0.200/Mtok input and $0.500/Mtok output, with a 2M-token context window. It supports text, image input.
Gemini 2.5 Flash by Google costs $0.075/Mtok input and $0.300/Mtok output, with a 1M-token context window. It supports text, image, audio, video input.
On a blended cost basis, Gemini 2.5 Flash is 86.7% cheaper than Grok 4.1 Fast.
On benchmarks, Grok 4.1 Fast scores higher (57 vs 53.7) on average. In terms of value, Gemini 2.5 Flash has better performance per dollar (286.4 vs 162.9).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.