Gemini 3 Flash vs Grok 4.20 Beta
Detailed pricing comparison and cost analysis.
Updated September 2026
Cost Simulator
| Feature | Gemini 3 Flash | Grok 4.20 Beta |
|---|---|---|
| Provider | xAI | |
| Input Price (1M) | $0.50 | $1.25 |
| Output Price (1M) | $3.00 | $2.50 |
| Context Window | 1,000,000 | 1,000,000 |
Verdict
Gemini 3 Flash costs $0.50 per 1M input tokens and $3.00 per 1M output tokens. Grok 4.20 Beta costs $1.25 per 1M input tokens and $2.50 per 1M output tokens. Gemini 3 Flash is 60% cheaper on input tokens than Grok 4.20 Beta. For output tokens, Grok 4.20 Beta is the more affordable option at $2.50/1M vs $3.00.
On context window, Gemini 3 Flash supports 1,000,000 tokens — meaning it can fit more conversation history, documents, or code in a single request. This matters for RAG pipelines, long document analysis, and agentic workflows where context builds up over many turns.
When to choose Gemini 3 Flash
- ✓ You need the lowest input token cost ($ 0.50/1M)
- ✓ You are already integrated with Google
When to choose Grok 4.20 Beta
- ✓ Your workload is output-heavy — Grok 4.20 Beta generates text cheaper
- ✓ You are already integrated with xAI
Use the calculator above to simulate your specific workload and find the exact break-even point. For most applications, the cheapest model is the one that minimises your total monthly bill given your input-to-output token ratio.
Frequently Asked Questions
Is Gemini 3 Flash cheaper than Grok 4.20 Beta? ▼
Gemini 3 Flash is cheaper on input tokens at $0.50/1M vs $1.25/1M for Grok 4.20 Beta — a 60% saving.
What is the context window of Gemini 3 Flash vs Grok 4.20 Beta? ▼
Gemini 3 Flash has a 1,000,000-token context window. Grok 4.20 Beta has a 1,000,000-token context window. Gemini 3 Flash supports the larger context, suitable for longer documents and agentic workflows.
Which model is better: Gemini 3 Flash or Grok 4.20 Beta? ▼
The best choice depends on your use case. For cost efficiency on input tokens, Gemini 3 Flash is the cheaper option. For maximum context length, Gemini 3 Flash supports 1,000,000 tokens. Use the comparison table above to find the right fit for your workload.