Gemini 2.5 Flash vs Grok 4.20 (Reasoning)
Both have similar output pricing, while Gemini 2.5 Flash offers a larger context window. Choose Gemini 2.5 Flash or Grok 4.20 (Reasoning) based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | Gemini 2.5 Flash | Grok 4.20 (Reasoning) |
|---|---|---|
| Provider | xAI | |
| Input / 1M tokens | $0.30 | $1.25 |
| Output / 1M tokens | $2.50 | $2.50 |
| Context window | 1M | 1M |
| Parameters | — | — |
| Open weights | No | No |
| Released | Jun 2025 | Mar 2026 |
| FrontierMath score | 4.8 | — |
| SWE-bench Verified score | 28.7 | — |
| Epoch Capabilities Index score | 143 | — |
| LMArena (Chatbot Arena) Elo score | 1417 | — |
| LMArena Vision Elo score | 1235 | — |
| LiveBench score | — | 69.0 |
FAQ
Is Gemini 2.5 Flash or Grok 4.20 (Reasoning) cheaper?
Gemini 2.5 Flash and Grok 4.20 (Reasoning) have comparable output pricing.
Which has the larger context window, Gemini 2.5 Flash or Grok 4.20 (Reasoning)?
Gemini 2.5 Flash has the larger context window (1M tokens).
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.