Last updated: 2026-09-23. Free tiers change often — every claim below links to the provider's own page, checked on that date.
An API key is a password that lets a program use an AI model on your account. On son-sunny.com you can paste your own key into your account and use the Workbench with it. Your key stays in your browser. Our site never receives it, and your requests go straight from your browser to the provider you chose. That also means the provider's limits and prices are yours, so it is worth picking the right one.
Which free option should you pick?
| Provider | Free? | The catch | Best for |
|---|---|---|---|
| Google Gemini | Yes, Flash models are free of charge | On the free tier, your prompts are used to improve Google's products | Most people: good quality, generous |
| Groq | Yes, a free plan | Limits are set per model | Speed |
| OpenRouter | Yes, models ending in :free | 50 requests a day until you buy credits | Trying many different models |
If you only get one, get Gemini. If what you write is private, read its catch first.
Google Gemini
Google's pricing page lists the current Flash models as free of charge on the free tier. The same page says that on the free tier, content is used to improve Google's products. So don't paste anything private, such as client work, personal details or unpublished drafts you care about. If you need that, check the paid-tier terms on the same page.
To get a key, sign in to Google AI Studio with a Google account and create an API key. It starts with AIza.
Groq
Groq runs open models very fast. It has a free plan whose limits depend on the model, from requests per minute up to tokens per day, all listed on that page. The model our Workbench uses by default, openai/gpt-oss-120b, is on Groq's list of production models.
To get a key, create one at console.groq.com/keys. It starts with gsk_.
OpenRouter
OpenRouter gives one key for hundreds of models. The free ones end in :free. Its limits page says free models allow 20 requests a minute and 50 a day. The daily cap rises to 1,000 once you have bought at least 10 credits. The free list changes: in September 2026 there were 21 free models, and some older ones had disappeared.
To get a key, create one at openrouter.ai/keys. It starts with sk-or-.
Gone: GitHub Models
Older guides, including earlier versions of our own tools, suggested using a GitHub token with GitHub Models. GitHub retired GitHub Models on 30 July 2026, and its documentation now says the inference API is no longer available to any customer. A GitHub token will not work for this any more.
Paying instead
If you would rather pay for a stronger model, OpenAI and Anthropic charge per use with no free tier. Set a monthly spending limit in their dashboards before you start.
Keep the key safe
- Treat it like a password. Anyone who has it can spend your quota, or your money on a paid plan.
- Only paste it into sites you trust. On son-sunny.com it is saved in your browser's storage on that device. Nothing is sent to us.
- On a shared or public computer, click Remove in Connections when you are done.
- If it leaks, delete it on the provider's key page and make a new one. The old one stops working at once.
- On a paid plan, set a spending limit, so a leaked key can't run up a bill.
Connect it on son-sunny.com
1. Open your account. You don't need to sign in to use your own key. 2. Under Connections, paste the key next to the provider and click Save key. 3. Click Test. If it answers, you are ready. If it fails, the message says why: usually a mistyped key, or a free limit reached for the day. 4. Scroll down to Workbench and write what you want.