Short answer
The original Gemini 3 Pro Preview API was shut down on March 9, 2026, so it has no current free API quota—or paid API access. Google’s model page identifies it as deprecated and shut down. This applies to that API model, not necessarily to every Gemini app feature or model labeled “Pro.” (Gemini 3 Pro Preview model page)
The Gemini app and Gemini API have separate access and limits. For app users without a Google AI plan, Google lists standard compute-based limits rather than a fixed prompt count. Those app limits are not a free API request allowance. (Gemini app limits)
Gemini app access versus API access
| Route | What to know |
|---|---|
| Original Gemini 3 Pro Preview API | Shut down March 9, 2026; it is not a model to budget for or integrate with now. (Model status) |
| Gemini app, no Google AI plan | Google describes “standard” compute-based limits. Usage varies with the prompt, model, features, and chat length; limits refresh every five hours until a weekly limit is reached. Google does not publish a fixed prompt allowance or the weekly cap amount in the cited help information. (App limits) |
| A “Pro” option in the app | Check the model menu to see which choices are available to your account. Google says Auto can select an available model and that users can manually choose another available model from the menu. An Auto-routed answer labeled Pro does not establish that you selected—or received—the original Gemini 3 Pro. (Model selection) |
| Current API alternative | Gemini 3.1 Pro Preview is a separate API model with the ID gemini-3.1-pro-preview. Its availability does not establish a free quota or price; check those separately. (Gemini 3.1 Pro Preview model page) |
To check app usage: open Settings → Usage limits in Gemini. To check model access, inspect the available-model menu separately. The model-selection guide is specifically for Android; menu details may differ across interfaces. (Usage limits, model selection)
To check API quotas: use the Gemini API rate-limits documentation and your project’s current limits. Google says API limits are applied per project, not per API key, and vary by model. App usage limits do not tell you your API quota. (Gemini API rate limits)
What to check before budgeting for a production API
The available pricing evidence here does not establish Gemini 3.1 Pro Preview’s specific rates or free-tier eligibility. Google’s pricing page distinguishes Free access to certain models from Paid access to advanced models, but that general description does not confirm this model’s eligibility or price. Check the model’s current entry on Google’s live Gemini API pricing page and verify the tier and rates for your own project. (API pricing information)
Before estimating spend, confirm:
- Whether your project can use the model on the Free tier or needs Paid access.
- The displayed currency, billing unit, and input and output rates.
- Any additional rate conditions shown for the model, such as different pricing by input size.
- Your project’s current rate limits and billing status.
Once you have the published rates, estimate cost from your own expected usage: (input tokens ÷ billing unit × input rate) + (output tokens ÷ billing unit × output rate). This is a calculation method, not a price estimate; use the live model-specific rates rather than a consumer Gemini subscription price. API tiers and consumer app plans are separate. (API pricing)
Is Gemini 3.1 Pro Preview suitable for your workload?
Google’s model page lists text, image, video, audio, and PDF inputs, text output, a 1,048,576-token input limit, and a 65,536-token output limit. It labels the model Preview. Check the current documentation for its status and specifications before relying on it for production. (Gemini 3.1 Pro Preview model page)
Bottom line: The original Gemini 3 Pro Preview API is shut down, so there is no free limit to use for that API model. Gemini app access is separate: check the model menu for available choices and Settings → Usage limits for your app allowance. For a successor API, verify project eligibility, quotas, and live model-specific rates before budgeting.
Sources
Gemini 3 Pro preview | Gemini API | Google AI for Developers
Gemini 3.1 Pro preview | Gemini API | Google AI for Developers
Rate limits | Gemini API | Google AI for Developers
Gemini Developer API pricing | Google AI Studio
Manage your Google AI plan from Gemini Apps