Payroll API

Rate limits

Every response carries the IETF draft rate-limit headers:

RateLimit-Limit: 300
RateLimit-Remaining: 288
RateLimit-Reset: 12

Limits are per API key, on a sliding window. Going over returns 429 rate_limited with a Retry-After header (seconds). Batch calculations (POST /v1/calculations/batch, up to 500 inputs) count as a single request against the limit — prefer batching over looping single calculations when you’re processing a whole payroll run.