Rate limits
A per-minute limit and a monthly request allowance that follows your plan.
Three limits sit in front of the API. They count requests, free ones included; credits are separate and only paid calls spend them (Credits and billing).
| Limit | Window | Applies to |
|---|---|---|
| 60 requests per minute | rolling 60 seconds | each key |
| The monthly request allowance | calendar month, refilled on the 1st at 00:00 UTC | each key |
| The same allowance across the account | rolling 30 days | all keys on the account |
The request allowance follows your workspace's plan: 150,000 requests a month with a plan,
9,000 without one. Credits do not change it: they are spent call by call, and a call without
credits answers 402. A key is issued with its workspace's allowance. Keys issued before the
allowance followed the plan are raised to it, and the account and its keys are raised again when
a plan starts. Nothing is ever lowered.
The account-wide allowance counts the last 30 days, not the calendar month. After a busy end of
a month it can still be used up when a key refills on the 1st; it frees up as the requests of
30 days ago fall out of the window, and its 429 says when in Retry-After.
Exhausting any of them answers 429 with code rate_limited and a Retry-After header; the
key is still valid. For a key's own allowance, Retry-After and X-RateLimit-Reset give that key's
next refill (a key issued with a fixed number of requests and no refill says so, without
Retry-After). Another key has its own monthly allowance but shares the account's, so it
does not help once the account's is spent. Raising an allowance beyond your
plan's: sales@registercheck.de.
Response headers
Successful responses carry the per-minute limit state:
X-RateLimit-Limit: 60
X-RateLimit-Remaining: 58
X-RateLimit-Reset: 2026-09-15T08:41:00Z
X-RateLimit-Provider: UnkeyThese headers describe the limit closest to being hit. The monthly allowance's balance is not currently exposed on a successful response.
Staying inside the limits
- Serialise your calls or cap concurrency at around 40 requests per minute; the per-minute ceiling is shared, so two workers at 40 each will trip it.
- Cache company records. Register entries change on the order of once a year, not once a minute — see Monitoring for the supported way to learn about changes instead of polling.
- Prefer one filter call over many single-company reads when you are building a list.