Gemini 3.1 Pro vs o4-mini

Gemini 3.1 Pro and o4-mini are both current production-tier models. o4-mini is meaningfully cheaper at $1.1 / $4.4 per 1M. Gemini 3.1 Pro has a 2M context window — about 10× the 200k of o4-mini. Gemini 3.1 Pro leads on general knowledge, long-context retrieval, multilingual.

Specs side by side

Metric
Google
Gemini 3.1 Pro
OpenAI
o4-mini
Input price (per 1M)$2$1.1
Output price (per 1M)$12$4.4
Context window2M tokens200k tokens
Speed tierbalancedslow
Open weightsNoNo
EU regionYesYes
Free tierNoNo
Prompt cachingYesYes
Vision inputYesYes
Extended thinkingYesYes

When to choose each

Google

Choose Gemini 3.1 Pro if…

  • You need 2M context (10× more than o4-mini)
  • General knowledge is central to your workload
  • Long-context retrieval is central to your workload
OpenAI

Choose o4-mini if…

  • Cost is a priority ($1.1 / $4.4 per 1M vs $2 / $12 per 1M)

Benchmark delta

Gemini 3.1 Pro leads on

  • General knowledge
  • Long-context retrieval
  • Multilingual
  • Vision

o4-mini leads on

o4-mini has no meaningful benchmark lead in this pair.

FAQ — Gemini 3.1 Pro vs o4-mini

Gemini 3.1 Pro vs o4-mini — which is better?

Gemini 3.1 Pro and o4-mini are both current production-tier models. o4-mini is meaningfully cheaper at $1.1 / $4.4 per 1M. Gemini 3.1 Pro has a 2M context window — about 10× the 200k of o4-mini. Gemini 3.1 Pro leads on general knowledge, long-context retrieval, multilingual. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.

How does Gemini 3.1 Pro pricing compare to o4-mini?

Gemini 3.1 Pro costs $2 / $12 per 1M vs o4-mini at $1.1 / $4.4 per 1M. o4-mini is cheaper on output tokens by roughly 173%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.

Does Gemini 3.1 Pro or o4-mini have the bigger context window?

Gemini 3.1 Pro has a 2M-token context window — 10× the 200k context of o4-mini. Enough for entire codebases, books, or multi-document RAG.

Is there a free tier for Gemini 3.1 Pro or o4-mini?

Gemini 3.1 Pro: no — Paid-only since 2026-04-01 (previously had free tier via AI Studio). o4-mini: no — Paid-only.

Which is better for coding — Gemini 3.1 Pro or o4-mini?

Gemini 3.1 Pro leads on coding benchmarks (Gemini 3.1 Pro: 94/100, o4-mini: 92/100). For production coding agents also weigh tool-use performance — Gemini 3.1 Pro scores 91, o4-mini scores 88.