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Gemini 3.1 Pro vs Gemini 3 Flash

Pricing, context window, and benchmark comparison · Last updated April 2026

Quick Verdict

Gemini 3 Flash is cheaper than Gemini 3.1 Pro at $0.50/1M/1M vs $2.00/1M/1M input tokens — a 4.0x cost difference. Gemini 3.1 Pro scores higher on quality benchmarks (ELO 1410). Choose Gemini 3 Flash for cost-sensitive workloads; choose Gemini 3.1 Pro for maximum quality.

Detailed Comparison

MetricGemini 3.1 ProGemini 3 Flash
Input Price / 1M tokens$2.00/1M$0.50/1MCheaper
Output Price / 1M tokens$12.00/1M$3.00/1MCheaper
Context Window1M1M
ELO Score (LMSYS)1410Smarter1370
Open Source
Free Tier
Release Date2026-032026-02

Which is cheaper: Gemini 3.1 Pro or Gemini 3 Flash?

Gemini 3 Flash is the cheaper option at $0.50/1M per 1M input tokens, compared to $2.00/1M for Gemini 3.1 Pro. That is a 4.0x cost difference on input tokens. Output pricing follows a similar pattern: Gemini 3.1 Pro charges $12.00/1M/1M vs $3.00/1M/1M for Gemini 3 Flash.

Which has better quality: Gemini 3.1 Pro or Gemini 3 Flash?

Based on LMSYS Chatbot Arena rankings, Gemini 3.1 Pro achieves a higher ELO score (1410 vs 1370), suggesting stronger performance on open-ended tasks. Gemini 3.1 Pro excels at google's latest flagship with major reasoning improvements. Gemini 3 Flash is known for gemini 3-generation quality at flash pricing.

Which should you choose: Gemini 3.1 Pro or Gemini 3 Flash?

Choose Gemini 3.1 Pro if:
  • Google's latest flagship with major reasoning improvements
  • 1M token context window
  • Native multimodal (text, image, video, audio)
Choose Gemini 3 Flash if:
  • Gemini 3-generation quality at Flash pricing
  • 1M context window
  • Strong multimodal reasoning

Frequently Asked Questions

Which is cheaper: Gemini 3.1 Pro or Gemini 3 Flash?

Gemini 3 Flash is cheaper at $0.50/1M per 1M input tokens, making it 4.0x more affordable.

Which has better quality: Gemini 3.1 Pro or Gemini 3 Flash?

Gemini 3.1 Pro scores higher on the LMSYS Chatbot Arena with an ELO of 1410, suggesting better overall quality for most tasks.

Which has a larger context window: Gemini 3.1 Pro or Gemini 3 Flash?

Both Gemini 3.1 Pro and Gemini 3 Flash have the same context window.

Should I choose Gemini 3.1 Pro or Gemini 3 Flash?

Choose Gemini 3 Flash if cost is the priority. Choose Gemini 3.1 Pro if benchmark quality is most important. Consider your specific use case: Gemini 3.1 Pro is best for reasoning and long-context, while Gemini 3 Flash excels at fast-response and function-calling.

Is Gemini 3.1 Pro or Gemini 3 Flash open source?

Gemini 3.1 Pro is proprietary. Gemini 3 Flash is proprietary.

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