Gemini 3.5 Flash vs Grok 4.1 Fast
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Gemini 3.5 Flash
Google · May 2026
Google's I/O 2026 headliner: near-Pro intelligence at Flash speed, 78.8% on SWE-bench Verified with full multimodal input.
Grok 4.1 Fast
xAI · Nov 2025
A 2M-token context window for $0.20 per million input tokens — the cheapest long-context frontier offering anywhere.
The verdict
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Grok 4.1 Fast works out roughly 12x cheaper per blended million tokens. Grok 4.1 Fast also takes 2M of context versus 1M for Gemini 3.5 Flash.
Specs & pricing
| Gemini 3.5 Flash | Grok 4.1 Fast | |
|---|---|---|
| modhub Index | — | — |
| Input price / 1M | $1.5 | $0.2 |
| Output price / 1M | $9 | $0.5 |
| Context window | 1M | 2M |
| Max output | 66K | — |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image, audio, video | text, image |
| Knowledge cutoff | Feb 2026 | Nov 2025 |
| Released | May 2026 | Nov 2025 |
| Example monthly cost* | $28.50 | $2.75 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Gemini 3.5 Flash or Grok 4.1 Fast?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Grok 4.1 Fast works out roughly 12x cheaper per blended million tokens. Grok 4.1 Fast also takes 2M of context versus 1M for Gemini 3.5 Flash.
- Which is cheaper, Gemini 3.5 Flash or Grok 4.1 Fast?
- Gemini 3.5 Flash costs $1.5/$9 per million input/output tokens, while Grok 4.1 Fast costs $0.2/$0.5. For a typical workload of 10M input and 1.5M output tokens per month, that's $28.50 versus $2.75.
- Which model is better for coding, Gemini 3.5 Flash or Grok 4.1 Fast?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.
More comparisons
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