Cron Explainer

cron-explainer

A tiny pay-per-call API that parses cron expressions, returns the next N fire times, and produces a short English description. Timezone-aware (IANA).

Live: https://cron-explainer.cron-explainer-prod.workers.dev/ Pricing: 0.01 EUR per successful call, prepaid via Stripe Checkout in packs of 500 / 5,000 / 50,000 calls. Non-2xx responses are refunded. No subscription. Keys never expire.

Quick start

1. Get a key at https://cron-explainer.cron-explainer-prod.workers.dev/ (Stripe Checkout, €5 minimum).
2. Copy the key — it's shown exactly once.
3. Call the API:

curl -X POST https://cron-explainer.cron-explainer-prod.workers.dev/v1/explain \
  -H "content-type: application/json" \
  -H "x-api-key: $YOUR_KEY" \
  -d '{"cron":"0 9 * * 1-5","tz":"Europe/Lisbon","n":3}'

Response:

{
  "input": {"cron":"0 9 * * 1-5","tz":"Europe/Lisbon","n":3},
  "valid": true,
  "description": "At 09:00, Monday through Friday",
  "next": ["2026-04-24T08:00:00.000Z","2026-04-27T08:00:00.000Z","2026-04-28T08:00:00.000Z"],
  "flags": {"dst_transition_ahead": false, "ambiguous": false, "notes": []},
  "errors": []
}

Check remaining balance:

View the full README on GitHub