429 Too Many Requests.
Limits
- 100 requests per minute
- 3,000 requests per hour
Stricter endpoints
Some endpoints have lower hourly limits than the default quotas, including:- Reporting:
/v3/reporting/* - Sequence statistics:
/v3/sequences/{id}/stats/v3/sequences/stats
429 Too Many Requests before the general limits are reached.
The 429 response
When a rate limit is exceeded, the API returns:- Status:
429 Too Many Requests - Headers:
Retry-After: <seconds>— seconds to wait before the quota window resetsContent-Type: application/problem+json
- Body:
detail reflect the limit that was exceeded, for example 3000 per 1h for the hourly quota.
Response headers
Successful responses include headers describing your current quota:
These headers are not included on
429 responses, which carry only Retry-After.
The headers report the longest-period limit that applies to the endpoint. A shorter limit, such as the per-minute quota, can return
429 while x-rate-limit-remaining still shows requests left, so don’t rely on these headers to predict a 429.Handling 429
1
Respect Retry-After
Wait for the number of seconds specified in the
Retry-After header before retrying the request.2
Limit concurrency
For bulk operations, process requests sequentially or use a small concurrency limit instead of sending many requests in parallel.