Gemini 3.1 Pro vs GPT-5.5 Pricing
Gemini 3.1 Pro Preview and GPT-5.5 are both strong candidates for long-context, agentic, and multimodal planning workloads. The pricing comparison is mostly about thresholds.
Official sources: Gemini API pricing and OpenAI pricing.
| Model | Short input / 1M | Short cache / 1M | Short output / 1M | Long input / 1M | Long output / 1M |
|---|---|---|---|---|---|
| Gemini 3.1 Pro Preview | $2.00 | $0.20 | $12.00 | $4.00 above 200K | $18.00 above 200K |
| GPT-5.5 | $5.00 | $0.50 | $30.00 | $10.00 above 200K | $45.00 above 200K |
Why Gemini looks cheaper
For both short and long prompt bands, Gemini 3.1 Pro Preview lists lower token rates than GPT-5.5. That makes it a strong candidate for retrieval, large-document analysis, and high-volume prompt processing.
Open the Gemini 3.1 Pro token calculator and compare it with GPT-5.5.
Why GPT-5.5 still needs a separate page
GPT-5.5 has OpenAI-specific operational modes: batch, flex, and priority. If your deployment already uses those routes, the effective cost and latency profile may not match a simple standard-price table.
Use the live Gemini 3.1 Pro vs GPT-5.5 pricing comparison for side-by-side numbers.
Practical rule
If the workload is mostly long input and moderate output, Gemini 3.1 Pro Preview is the cheaper listed option. If the workflow depends on OpenAI tooling, model behavior, or priority processing, calculate the real operating path before migrating.