Gemini 3.1 Flash-Lite vs Grok 4.20
Gemini 3.1 Flash-Lite and Grok 4.20 are both current production-tier models. Gemini 3.1 Flash-Lite is meaningfully cheaper at $0.25 / $1.5 per 1M. Grok 4.20 leads on coding, reasoning, general knowledge.
Specs side by side
| Metric | Google Gemini 3.1 Flash-Lite | xAI Grok 4.20 |
|---|---|---|
| Input price (per 1M) | $0.25 | $2 |
| Output price (per 1M) | $1.5 | $6 |
| Context window | 1M tokens | 2M tokens |
| Speed tier | ultra | balanced |
| Open weights | No | No |
| EU region | Yes | No |
| Free tier | Google AI Studio | No |
| Prompt caching | No | Yes |
| Vision input | Yes | Yes |
| Extended thinking | No | Yes |
When to choose each
Choose Gemini 3.1 Flash-Lite if…
- Cost is a priority ($0.25 / $1.5 per 1M vs $2 / $6 per 1M)
- Low latency matters (ultra vs balanced)
- EU data residency is required
- You want a free tier for prototyping
Choose Grok 4.20 if…
- You need 2M context (2× more than Gemini 3.1 Flash-Lite)
- Coding is central to your workload
- Reasoning is central to your workload
Benchmark delta
Gemini 3.1 Flash-Lite leads on
Gemini 3.1 Flash-Lite has no meaningful benchmark lead in this pair.
Grok 4.20 leads on
- Coding
- Reasoning
- General knowledge
- Instruction following
- Vision
- Tool use
FAQ — Gemini 3.1 Flash-Lite vs Grok 4.20
Gemini 3.1 Flash-Lite vs Grok 4.20 — which is better?
Gemini 3.1 Flash-Lite and Grok 4.20 are both current production-tier models. Gemini 3.1 Flash-Lite is meaningfully cheaper at $0.25 / $1.5 per 1M. Grok 4.20 leads on coding, reasoning, general knowledge. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.
How does Gemini 3.1 Flash-Lite pricing compare to Grok 4.20?
Gemini 3.1 Flash-Lite costs $0.25 / $1.5 per 1M vs Grok 4.20 at $2 / $6 per 1M. Gemini 3.1 Flash-Lite is cheaper on output tokens by roughly 300%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does Gemini 3.1 Flash-Lite or Grok 4.20 have the bigger context window?
Grok 4.20 has a 2M-token context window — 2× the 1M context of Gemini 3.1 Flash-Lite. Enough for entire codebases, books, or multi-document RAG.
Is there a free tier for Gemini 3.1 Flash-Lite or Grok 4.20?
Gemini 3.1 Flash-Lite: yes — Reduced daily quota; most generous free tier of any frontier lab. Grok 4.20: no — X Premium includes Grok web chat; API is paid.
Which is better for coding — Gemini 3.1 Flash-Lite or Grok 4.20?
Grok 4.20 leads on coding benchmarks (Gemini 3.1 Flash-Lite: 72/100, Grok 4.20: 91/100). For production coding agents also weigh tool-use performance — Gemini 3.1 Flash-Lite scores 76, Grok 4.20 scores 88.