specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: Certn
providerId: certn
created: '2026-07-03'
modified: '2026-07-03'
reconciled: false
tags:
- Background Checks
- Screening
- Rate Limiting
- Quotas
- Webhooks
description: >-
  Certn does not publish fixed numeric per-minute or per-day rate limits for its
  REST API in the public developer documentation. In practice the API is
  order-oriented (you create applications and poll or receive webhooks for
  results) rather than high-frequency, so throughput is effectively governed by
  your account configuration and the pace at which checks are ordered rather than
  a documented request cap. Webhook delivery has a defined retry policy: on a
  408, 500, 502, 503, or 504 response from your endpoint, Certn retries up to
  three additional times with increasing back-off between attempts.
notes: >-
  No numeric per-account or per-endpoint request-rate limit is documented as of
  the review date. Assume standard 429 throttling may apply under abuse and
  implement exponential backoff. Confirm any contractual throughput limits with
  Certn for high-volume integrations. List endpoints are paginated (offset/limit)
  which bounds per-request payload size.
sources:
- https://docs.certn.co/api
- https://docs.certn.co/api/guides/use-the-api/webhooks
- https://docs.certn.co/api/api-reference/hr
responseCodes:
  throttled: 429
limits:
- name: REST API Requests
  scope: account
  metric: requests
  limit: not published
  notes: No fixed numeric request-rate limit is documented for the Certn REST API.
- name: List Pagination
  scope: request
  metric: records
  limit: paginated via offset/limit
  notes: Applicant/report list endpoints return results in paginated pages.
- name: Webhook Delivery Retries
  scope: webhook
  metric: attempts
  limit: 3 additional retries
  notes: On 408/500/502/503/504 from your endpoint, Certn retries up to three more times with increasing back-off.
policies:
- name: Webhook Retry and Back-off
  description: Failed webhook deliveries (408/500/502/503/504) are retried up to three additional times, waiting longer between each call; other 4xx responses trigger immediate back-off without retry.
- name: Signature Verification
  description: Each webhook carries a Certn-Signature header (HMAC-SHA256 over timestamp + payload) with a fresh timestamp per attempt to prevent replay; verify with constant-time comparison.
- name: Backoff Strategy
  description: Clients should implement exponential backoff with jitter and honor Retry-After if a 429 is returned.
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com