GPT-5.5 Pro vs Gemini 3.1 Pro — Pricing Comparison 2026

Requests per Day

Days per Month

OpenAI

GPT-5.5 Pro

$0.00

per month

Input cost

Output cost

Cost per request

Requests/month

Google

Gemini 3.1 Pro

$0.00

per month

Input cost

Output cost

Cost per request

Requests/month

Which Model for Which Use Case?

Cost Optimization

Gemini 3.1 Pro at $2.00/M input is 93% cheaper than GPT-5.5 Pro. For any workload where cost matters, Gemini 3.1 Pro delivers massive savings.

Best value: Gemini 3.1 Pro (93% cheaper)

Maximum Reasoning

GPT-5.5 Pro is OpenAI's most powerful model with cutting-edge reasoning. If you need the absolute best performance and budget is not a concern, GPT-5.5 Pro is the choice.

Top performance: GPT-5.5 Pro | Value: Gemini 3.1 Pro

Context Window

GPT-5.5 Pro has 1.05M context vs Gemini 3.1 Pro's 1M. The 5% difference is negligible for most workloads — both handle very long documents well.

Either model works for long context

Enterprise Workloads

Gemini 3.1 Pro offers Google Cloud integration at 93% lower cost. GPT-5.5 Pro provides OpenAI's premium capabilities for mission-critical tasks where performance is paramount.

Cost-sensitive enterprise: Gemini | Mission-critical: GPT-5.5 Pro

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Frequently Asked Questions

Is Gemini 3.1 Pro cheaper than GPT-5.5 Pro?

Yes. Gemini 3.1 Pro costs $2.00/M input and $12.00/M output. GPT-5.5 Pro costs $30.00/M input and $180.00/M output. Gemini 3.1 Pro is 93% cheaper on both input and output. For 1M input + 500K output/month, Gemini 3.1 Pro costs $8.00 vs GPT-5.5 Pro's $120.00 — saving $112.00/month (93%).

Which has a larger context window?

GPT-5.5 Pro has a 1.05M token context window — 5% larger than Gemini 3.1 Pro's 1M context. The difference is minimal; both handle very long documents well.

When should I choose GPT-5.5 Pro over Gemini 3.1 Pro?

Choose GPT-5.5 Pro when: (1) you need the absolute highest reasoning capability, (2) budget is not a concern, (3) your workload requires cutting-edge performance. Choose Gemini 3.1 Pro when: (1) cost matters (93% cheaper), (2) you want Google's ecosystem, (3) your workload fits within 1M context.

Are both models production-ready?

Both are production-ready. GPT-5.5 Pro is OpenAI's most powerful model with 1.05M context and top-tier reasoning. Gemini 3.1 Pro is Google's mid-tier model with 1M context and strong capabilities at a fraction of the cost.