Get a Google Gemini API key

Before you start

Gemini is Google's AI. A key from Google AI Studio works on the free tier straight away, with no payment.

• A Google account. A school or work account may not be allowed to use AI Studio (its administrator decides, and school accounts of people under 18 cannot use it). Then use a personal Google account.
• You must be 18 or older.
• On the free tier, Google may use what you send to improve its products, and people at Google may read it. On the paid tier it does not. In the European Economic Area, Switzerland and the United Kingdom, Google treats free use like paid use. For a manuscript under review or anything confidential, move to the paid tier first.
• The free tier has limits per minute and per day. The daily limit comes back after midnight, US Pacific time.
• Gemini is not offered in every country or region: Google's list.

These steps follow Google's own documentation as of 2026-10-23 (sources at the end). The exact wording of buttons can change.

1. Open Google AI Studio

Open aistudio.google.com/apikey and sign in with your Google account. The first time, agree to the terms. In Rectoly, Get a key opens this page.

2. Create a key

A new account gets a project and a key by itself once you agree to the terms; if a key is listed, you can use it. Otherwise press Create API key (choose the project if asked).

3. Copy the key

Open the key in the list and copy it.

4. Paste it into Rectoly

In Rectoly, open Settings › AI and choose Your own API key (the first time, read the notice and agree). Under Quick setup, choose Google Gemini as the AI company and press Paste and check. When In use: appears, you are done. More: Paste the key into Rectoly.

Move to the paid tier

Do this when you reach the free tier's limits, or when you do not want Google to use what you send.

1. In AI Studio, find your project and press Set up billing in the Billing Tier column.
2. Choose your country and enter your contact details and a payment method.
3. New accounts pay in advance: add at least US$5. When that runs out, Gemini stops taking requests until you add more.

• On the Spend page you can set a Monthly spend cap for the project.
• What one paper costs: What it costs.

If the key is not accepted

Google no longer accepts older keys that have no restrictions. A key created in AI Studio today is fine; if an older key stops working, create a new one in AI Studio and paste that.

Delete the key

Delete the key on the API keys page in AI Studio. A deleted key no longer works anywhere, Rectoly included.