On the Free plan, you can use your own OpenAI, Google Gemini or Anthropic Claude API key in the Jetwriter AI extension. Open Jetwriter, click your profile icon, choose Settings, and turn on Use your own API key under Advanced. Replies written with your key don't count toward your 15 free AI responses, and the company the key is from bills you for them. The setting is in the extension only, and only on the Free plan.
For where to get a key from each company, see Use your own API key.
Add your key
- Open Jetwriter: click its icon in your browser's toolbar, or press Ctrl+Shift+K (Cmd+Shift+K on a Mac).
- Click your profile icon at the top of the Jetwriter window, then Settings.
- Scroll down to Advanced and turn on Use your own API key.
- Paste your key into OpenAI API key, Google (Gemini) API key or Anthropic (Claude) API key, and click Save. Jetwriter checks the key with that company (the button shows Verifying), then shows Saved.
- In the model picker at the bottom left of the box where you type, pick a model from that company.
You can add a key from one company or from all three.
The models each key unlocks
| Key | Models you can pick |
|---|---|
| OpenAI API key | GPT 6 Sol and GPT 6 Luna |
| Google (Gemini) API key | Gemini 3.1 Pro and Gemini 3 Flash |
| Anthropic (Claude) API key | Opus 5.5, Sonnet 5.5 and Haiku 5.5 |
While a key is saved, only the models of the companies you added a key for can be picked: the others show a lock, including the Free plan's own models. For example, with only an OpenAI key, Haiku 5.5 and Gemini 3 Flash are locked too. To pick them again, turn off Use your own API key. For how the model picker and thinking levels work, see Pick an AI model and thinking level.
What changes with your own key
- No 15-response limit for these replies. They don't count toward your free responses, and the counter of responses left (such as 12/15 left) next to the send button hides.
- The company bills you. Each reply is charged to your account with OpenAI, Google or Anthropic, at their prices, so you need a payment method there.
- Some features are off for these replies. Jetwriter doesn't search the web or read web pages for them, and Memory ("Reference past conversations") in Settings is turned off and locked.
- The web app doesn't use your key. At jetwriter.ai/app, replies count toward your 15 free responses as usual.
- You still need a free Jetwriter account, signed in and with a verified email.
The setting says "Your API key is stored locally in your browser and is never saved on our servers." Jetwriter sends it, encrypted, with each reply that uses it.
If your key shows an error
- When you save the key: if the company refuses it, its own error message shows under the box. Check that you copied the whole key, that it's active, and that billing is set up in your account with that company. Then click Save again.
- When you write a reply: if the company refuses the request, for example because your credit ran out or you sent too many requests at once, Jetwriter shows the company's error message in its window. Fix it in your account with that company, or turn off Use your own API key to write with your free responses.
Remove your key
- To remove one key, click Remove next to it.
- To stop using your keys, turn off Use your own API key. That removes every key you saved, and replies count toward your 15 free responses again.
If you upgrade to Elite or Ultra, the setting disappears and your keys aren't used: paid plans include Jetwriter's own AI.