Cron Jobs

Run periodic tasks on a schedule you define.

You can create cron jobs on Render that run periodically on a schedule you define. You create cron jobs in the Render Dashboard, just like you create any other service type:

Creating a cron job in the Render Dashboard

Your cron job can use any of your connected repos, or it can pull a prebuilt Docker image from an external registry.

  • If you connect a Git repo, Render builds a new version of your code whenever you push changes to your connected branch. The new build does not affect in-progress runs (only future runs).
  • If you pull a Docker image, Render pulls that image before each run of your cron job. Render does not retain pulled images between runs.

Cron jobs can't provision or access a persistent disk.

Setup

The cron job setup flow is similar to that of other service types, but with a couple of fields specific to cron jobs:

Cron-job-specific settings in the Render Dashboard
FieldDescription

Schedule

The schedule to use for the cron job, defined as a cron expression.

Here are some examples:

  • Every ten minutes: */10 * * * *
  • Once every day at noon UTC: 0 12 * * *
  • Once every 60 minutes, Monday through Friday UTC: */60 * * * MON-FRI

All day and time ranges use UTC.

Command

The command to execute with each run. This can be:

  • Any valid Linux command, such as echo "Hello!"
  • An executable bash script that contains the command(s) to run

Make sure to use a command that exits when it's done! Like other service types, cron jobs are billed according to how long they run.

This field is not present for Docker-based cron jobs.

Instead, Render defaults to running your Docker image's startup command (as defined by ENTRYPOINT and/or CMD in your Dockerfile).

You can override this by setting a custom Docker Command under Advanced in the creation flow.

After creating your cron job, you can track build progress and history on the Builds page. Your cron job's Runs page shows run history and logs for each run.

Environment variables

Like any other Render service, cron jobs can set environment variables for values like database URLs and API keys. You can also share environment variables across multiple services with an environment group.

Manually triggering a run

To run your cron job at an unscheduled time (such as for debugging purposes), go to its Runs page in the Render Dashboard and click Trigger Run.

If you manually trigger a cron job run while another run is active, Render first cancels the active run. For details, see Single-run guarantee.

Single-run guarantee

Render guarantees that at most one run of a given cron job is active at a given time. This protects against issues that can arise with parallel execution.

What if I manually trigger a run while another run is active?

Render immediately cancels the active run, then starts the manually triggered run.

What if a run is currently active at the time of the next scheduled run?

Render delays the next scheduled run until the active run finishes.

What if my run never finishes or takes a very long time?

Render stops an active run after 12 hours. To perform tasks that run longer than this (or continuously), instead create a workflow or background worker.

Compute plans and billing

Cron jobs can use whichever compute plan best suits their CPU and memory requirements. Billing is prorated by the second, based on active running time during a given month.

There is a minimum monthly charge of $1 per cron job service.