Primitives Cron
Cron API
Cron syntax, zero daemons. Define your schedule with familiar cron expressions — we invoke your webhook on time, every time.
Cron expression RocketStack Your webhook
Quickstart
Create a cron job and have it run on your schedule automatically.
1. Create a cron job
Define your schedule with standard cron syntax.
POST https://api.rocketstack.dev/cron
{
"name": "daily-report",
"schedule": { "expression": "0 9 * * 1-5" },
"deliveryTarget": {
"type": "webhook",
"webhookUrl": "https://yourapp.com/daily-report"
}
}2. Add payload (optional)
Include context data sent with each invocation.
POST https://api.rocketstack.dev/cron
{
"name": "nightly-cleanup",
"schedule": { "expression": "0 2 * * *" },
"deliveryTarget": {
"type": "webhook",
"webhookUrl": "https://yourapp.com/cleanup"
},
"payloadTemplate": { "type": "nightly" }
}3. Receive invocations
Your webhook is called on schedule, every time.
// Every weekday at 9 AM UTC:
POST https://yourapp.com/daily-report
{
"cronJobId": "cron_abc123",
"scheduledAt": "2025-02-10T09:00:00Z"
}Cron Syntax
Standard 5-field cron expressions.
Cron expression
┌───────────── minute (0 - 59)
│ ┌───────────── hour (0 - 23)
│ │ ┌───────────── day of month (1 - 31)
│ │ │ ┌───────────── month (1 - 12)
│ │ │ │ ┌───────────── day of week (0 - 6, Sun = 0)
│ │ │ │ │
* * * * *0 9 * * *Every day at 9 AM0 9 * * 1-5Weekdays at 9 AM*/15 * * * *Every 15 minutes0 0 1 * *First day of every month at midnightFeatures
Everything you need for scheduled jobs.
Standard cron syntax
Familiar 5-field expressions. If you know cron, you already know how to use it.
Webhook invocation
We trigger your endpoint on schedule. Retries on failure included.
Optional payload
Pass context with each invocation. Know which job triggered the call.
No server maintenance
Zero cron daemons to manage. No servers, no VMs, no containers.
Limits & Quotas
Generous defaults for most workloads.
| Resource | Limit |
|---|---|
| Minimum interval | 1 minute |
| Maximum cron jobs | 1,000 per account |
| Payload size | 1 MB |
| Timezone support | All IANA timezones |
| Webhook timeout | 30 seconds |
Use Cases
Common patterns for the Cron API.
Nightly syncs
Sync data between systems every night. Pull from APIs, update databases, refresh caches.
Cleanup jobs
Delete expired sessions, archive old records, clean up temporary files on a schedule.
Report generation
Generate and send daily, weekly, or monthly reports. Email dashboards to stakeholders.
Ready to create your first cron job?
Get your API key and start scheduling jobs in minutes.