# Credits

Credits cover overflow beyond your account's request-rate or free validation quota. One credit covers one HTTP request, even if it crosses more than one of those limits.

Buy packs in [Billing](https://disify.com/account/billing); see [pricing](https://disify.com/pricing). Credits require an [API key](https://docs.disify.com/guide/authentication.md) and are not available for anonymous requests.

## When a credit is spent

A credit is consumed only when you hit a limit and have a pack with credits remaining:

- **Per-minute rate limit** — a burst above your tier's [rate limit](https://docs.disify.com/guide/rate-limits.md) spends a credit instead of failing.
- **Free validation quota** — once a free account exhausts its daily or monthly address allowance, a further HTTP request spends one credit rather than being rejected.

Credits do not unlock premium features, raise per-request bulk limits, or bypass async-job limits and access restrictions.

If a request is served from credits, the response carries:

```
X-Credit-Used: true
```

Requests that stay within your normal limits **never** touch credits.

## How packs are drawn down

- One credit = one request.
- Bulk quota counts unique entries, but one overflow credit covers the HTTP request. The batch must still fit your tier's per-request limit.
- If that request exceeds more than one limit, it still spends only one credit.
- Packs are consumed **oldest-first**, by purchase date.
- Purchased credits **don't expire** — a pack stays usable until it's drawn down.
- When no credits remain, the normal rate or quota response applies. See [Error Handling](https://docs.disify.com/api/errors.md).

## Do you need credits?

| Situation | Better option |
| --- | --- |
| Steady, predictable volume above your tier | Upgrade to a higher [tier](https://docs.disify.com/guide/authentication.md) |
| Occasional spikes over your rate limit | Keep a credit pack on hand |
| One-off [bulk](https://docs.disify.com/api/bulk.md) run within your tier's batch limit | Credits can cover rate or quota overflow |

**Watch the header**

Log the `X-Credit-Used` header so you can see when you're dipping into credits — a steady stream of credit-served requests usually means it's time to move up a tier.

Source: https://docs.disify.com/guide/credits.html