1
Create an account
In your browser: openrouter.ai
- Type
openrouter.aiinto your browser’s address bar and press Enter. - Click “Sign in” in the top right.
Before you start: two terms, nothing more
- OpenRouter
- A middleman for AI. Instead of keeping a separate account with every provider (OpenAI, Google, DeepSeek …), you top up credits here once – and your Companion draws on them, no matter which model it uses.
- API key
- A long string of characters that works like a key: whoever has it can use AI models at your expense. It always starts with
sk-or-v1-.
Full cost control:
OpenRouter works with credits (prepaid) – like a phone top-up card. It can never spend more than you have loaded. Small amounts last surprisingly long.
The images are example sketches.
OpenRouter changes the look of its pages from time to time. Buttons may therefore look slightly different – the terms, however, stay the same.
2
Sign in – easiest with Google
In the sign-in window
- Most convenient: click “Continue with Google” and pick your Google account – done, no new password needed.
- Alternatively: enter your email address, click “Continue” and follow the instructions (watch for the confirmation email).
Does signing up cost anything? No. The account itself is free – you only pay for the credits in the next step, and only as much as you decide yourself.
3
Add credits
Click your profile picture in the top right → Credits
- Click your profile picture in the top right and choose “Credits”.
- Click “Add Credits”.
- Choose an amount – $10 is a good start – and complete the payment by card (securely processed by the payment service Stripe).
Why credits at all? The AI models bill by usage – usually fractions of a cent per request. Without credits, the key will later only work with a few free models, which are often slow or overloaded. How quickly the credits shrink depends above all on the chosen model – more on that in a moment.
4
Create the key
Profile picture → Keys – or directly: openrouter.ai/settings/keys
- Open “Keys” via your profile picture.
- Click “Create Key”.
- Name: anything you like, e.g. your Companion’s name. Credit limit (optional): here you can set how many credits this one key may use at most – a sensible safeguard, e.g.
10. - Click “Create”.
5
Copy the key right away and store it safely
In the window that appears right after creating
- Your new key is now displayed – it starts with
sk-or-v1-. It is shown only this one time! - Click the copy icon 📋 next to the key.
- Paste it into a safe place right away: a password manager, or a text file that lives only on your computer. Only then close the window.
Closed the window too soon? No big deal – but the key cannot be shown again. The fix: delete the old key in the list (trash icon) and simply create a new one. It costs nothing.
Done!
Your OpenRouter key is ready to use. Hand it to the program that needs it – for example by pasting it (Ctrl+V) into the field your Companion provides for it. You can check your balance and usage at any time under “Credits” and “Activity”.
Choosing a model: the biggest cost lever
AI models bill by usage – but not all at the same price. Between the cheapest and the most expensive model there can easily be a factor of fifty to a hundred per request. In everyday use you often barely notice a difference in quality – on your balance, all the more.
Recommended and already preset: DeepSeek V4 Pro
Your Companion comes set to this model out of the box: strong in everyday use, fast and very inexpensive – your $10 of credits last for weeks with it. Our recommendation: simply stick with it.
Other models: switch only deliberately
Switching models only pays off for special cases – and ideally after checking with the person who looks after your Companion. Don’t forget to switch back afterwards.
Careful with premium models (e.g. Claude Opus 4.8)
These top models are brilliant for complex special tasks – but cost many times more per request. Casually chatting with them can burn through €20 of credits in half an hour. For normal chats they are simply the wrong choice.
Important: how to handle the key
The key is like a money card with credit on it.
Please don’t put it on the public internet, don’t post it in forums or chat groups, and don’t send it by unencrypted email. If the key ever does fall into the wrong hands: delete it under “Keys” and create a new one – the old one is instantly worthless, your credits remain.
Common stumbling blocks
I forgot to copy the key
For security reasons, the key is shown only once. Delete the old entry in the key list and simply create a new one – it takes 30 seconds and costs nothing.
The Companion reports “Insufficient credits” or error 402
The credits are used up or the key’s limit has been reached. Add new credits under “Credits” or raise the key’s limit under “Keys”.
The key doesn’t work (“Invalid API key” / error 401)
Usually a copying error: a character is missing, or a space came along at the start or end. Safest fix: delete the old key, create a new one, and this time copy it with the copy icon 📋 instead of selecting it by hand.
How many credits do I need?
For a personal Companion in everyday use, $10 often lasts several weeks to months – depending on model and usage. You can see your usage at any time under “Activity” and simply top up when it runs low.
My credits are suddenly shrinking very fast
Almost always the model was switched. Check your Companion’s model setting and set it back to DeepSeek V4 Pro – the preset, inexpensive everyday model. Under “Activity” on OpenRouter you can see exactly which model used how much.
What the terms on the site mean
The most important ones: “Sign in” = log in to your account, “Credits” = your prepaid balance, “Add Credits” = top up that balance, “Keys” = your API keys, “Create” = create one, “Activity” = your usage overview, “Delete” = remove a key.