# Billing

> Manage your subscription, check your AI credits, and buy more when you need them.

This page shows you where to manage your Proferex subscription, how to check your AI credits, and how to buy more.

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## Manage your subscription

Click your name at the bottom of the sidebar and choose **Billing**.

![The menu under your name at the bottom of the sidebar, showing your AI credits, and Home, Account, Billing, and Log out](/images/docs/account-user-menu.jpg "Billing is in the menu under your name")

Proferex opens your billing page at our payment provider, Stripe. There you can:

- Update your card or other payment method.
- See and download your invoices.
- Change or cancel your subscription.

For our plans and prices, see [Pricing](/#pricing).

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## AI credits

AI credits pay for the [Tracker Agent](/docs/ai-assistant/agent-chat/index.md). Each reply uses credits for the work it does: a quick answer costs a little, and longer research costs more.

Your plan adds credits every month, including on yearly plans. Plan credits you don't use don't carry over.

To see your balance, click your name at the bottom of the sidebar. The menu shows your credits. For more detail, choose **Account** and open the **AI Credits** tab.

![The AI Credits tab of the Account page, showing 1,000 AI credits remaining and a Buy more credits slider set to $25 for 2,500 credits](/images/docs/account-ai-credits-buy.jpg "Account → AI Credits")

When your balance reaches zero, the Tracker Agent pauses until you buy more credits or your plan refills.

### Buy more credits

If you need more credits before your plan refills, buy them on the same **AI Credits** tab, under **Buy more credits**.

1. Drag the slider to choose an amount between $10 and $500, in $5 steps. Every $1 buys 100 credits, so $25 buys 2,500.
2. Click **Buy**. The button shows the credits and the price, for example **Buy 2,500 credits for $25**.
3. Pay at Stripe. You come back to the AI Credits tab, and the credits are added as soon as the payment clears, usually within a minute.

Bought credits never expire. The Tracker Agent uses your monthly plan credits first, and only uses bought credits when those run out.

> **Note:** AI credits, including ones you bought, need an active plan. If your plan has ended, reactivate it on your billing page to use the Tracker Agent again.

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## Next step

Open **Billing** and check that your payment method is up to date.