Gemini 3.1 Flash-Lite vs GPT-5.6 Luna
Gemini 3.1 Flash-Lite and GPT-5.6 Luna are both current production-tier models. Gemini 3.1 Flash-Lite is meaningfully cheaper at $0.25 / $1.5 per 1M. GPT-5.6 Luna leads on coding, reasoning, general knowledge.
Specs side by side
| Metric | Google Gemini 3.1 Flash-Lite | OpenAI GPT-5.6 Luna |
|---|---|---|
| Input price (per 1M) | $0.25 | $1 |
| Output price (per 1M) | $1.5 | $6 |
| Context window | 1M tokens | 1.1M tokens |
| Speed tier | ultra | fast |
| Open weights | No | No |
| EU region | Yes | Yes |
| 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 $1 / $6 per 1M)
- You want a free tier for prototyping
Choose GPT-5.6 Luna if…
- HIPAA eligibility is required
- 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.
GPT-5.6 Luna leads on
- Coding
- Reasoning
- General knowledge
- Instruction following
- Vision
- Tool use
FAQ — Gemini 3.1 Flash-Lite vs GPT-5.6 Luna
Gemini 3.1 Flash-Lite vs GPT-5.6 Luna — which is better?
Gemini 3.1 Flash-Lite and GPT-5.6 Luna are both current production-tier models. Gemini 3.1 Flash-Lite is meaningfully cheaper at $0.25 / $1.5 per 1M. GPT-5.6 Luna 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 GPT-5.6 Luna?
Gemini 3.1 Flash-Lite costs $0.25 / $1.5 per 1M vs GPT-5.6 Luna at $1 / $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 GPT-5.6 Luna have the bigger context window?
GPT-5.6 Luna has a 1.1M-token context window — 1× 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 GPT-5.6 Luna?
Gemini 3.1 Flash-Lite: yes — Reduced daily quota; most generous free tier of any frontier lab. GPT-5.6 Luna: no — Low-cost at $1/$6 per 1M; starter credits only.
Which is better for coding — Gemini 3.1 Flash-Lite or GPT-5.6 Luna?
GPT-5.6 Luna leads on coding benchmarks (Gemini 3.1 Flash-Lite: 72/100, GPT-5.6 Luna: 85/100). For production coding agents also weigh tool-use performance — Gemini 3.1 Flash-Lite scores 76, GPT-5.6 Luna scores 87.