Get a Google (Gemini) API key

Google builds the Gemini family of models. The fastest way to get an API key is through Google AI Studio -- no credit card required for the free tier.

Create your key

1. 1
   Sign in at aistudio.google.com

   Go to aistudio.google.com and sign in with any Google account (Gmail or Google Workspace). Accept the Terms of Service on your first visit.
2. 2
   Get your API key

   Click Get API key in the left sidebar (direct link: aistudio.google.com/app/apikey). Google may auto-create a default key for you. Otherwise click Create API key and select or create a Google Cloud project.
3. 3
   Copy the key

   Copy the key and store it somewhere safe. Google AI Studio keys start with AIza and are 39 characters long. Unlike Anthropic and OpenAI, you can view the key again later in the AI Studio dashboard.

Add it to Prompt Assay

Open Workspace Settings > Provider Keys, select Google, paste the key, click Test, then Save. See Adding and testing a provider key for the full walkthrough.

Free tier details

Google AI Studio offers a free tier with no credit card required. You get access to Gemini Flash and Pro models with per-minute rate limits (e.g. 10 requests/minute for Gemini 2.5 Flash). For higher rate limits, enable billing on the associated Google Cloud project.

Good to know

• EU/EEA, UK, and Switzerland: the free tier is not available in these regions. You must enable paid billing on your Google Cloud project to use the Gemini API from these locations.
• All keys under the same Google Cloud project share a single quota pool. Creating multiple keys does not multiply your rate limits.
• Prompts and responses on the free tier may be used by Google to improve their products. Paid tiers opt out of this.
• Google is the lowest-friction starting point -- if you want to try Prompt Assay without entering a credit card, start here.