Side-by-side technical and economic comparison between xAI's Grok 4.6 and Google's Gemini 2.5 Flash.
| Metric | Grok 4.6 | Gemini 2.5 Flash | Advantage |
|---|---|---|---|
| Provider Organization | xAI | — | |
| Standard Input / 1M | $2.00 | $0.30 | Gemini 2.5 Flash (85% lower) |
| Cached Input / 1M | $0.50 | $0.03 | Gemini 2.5 Flash lower |
| Output / 1M | $6.00 | $2.50 | Gemini 2.5 Flash lower |
| Context Window | 500k | 1.05M | Gemini 2.5 Flash (1.05M) |
| Max Generation Tokens | 128k | 8.2k | Grok 4.6 |
| Tokenizer Family | xAI Byte-level BPE (~131k vocabulary) | Google Gemma SentencePiece (~256k vocabulary) | — |
Opt for Grok 4.6 when your engineering requirements prioritize xAI's ecosystem, specific tokenizer efficiencies (Calibrated xAI Tokenizer (±3%)), or when your expected prompt-to-completion ratios favor its $2/M input rate.
Opt for Gemini 2.5 Flash when looking for Google's tooling integration, specific context window depth (1.05M tokens), or when output generation volume favors its $2.5/M rate.