Cron Every 30 Minutes
Schedule a cron job every 30 minutes using */30 * * * *. Complete field-by-field explanation with practical use cases and best practices.
Cron Expression
*/30 * * * *
Field Breakdown
| Field | Value | Meaning |
|---|---|---|
| Minute | */30 | Every 30th minute |
| Hour | * | Every hour (0–23) |
| Day of Month | * | Every day of the month (1–31) |
| Month | * | Every month (1–12) |
| Day of Week | * | Every day of the week (Sun–Sat) |
Detailed Explanation
The cron expression */30 * * * * schedules a task to run once every thirty minutes, all day, every day of the year.
Field-by-field breakdown:
*/30(Minute): Every 30th minute, starting from minute 0. The step value/30triggers execution at minutes 0 and 30 of each hour.*(Hour): Every hour from 0 through 23. No restriction on which hour.*(Day of Month): Every day from 1 through 31. No restriction on the day of the month.*(Month): Every month from January through December. No restriction on the month.*(Day of Week): Every day of the week from Sunday through Saturday. No restriction on the day.
This means your task will execute 48 times per day, or twice per hour. The half-hour schedule is one of the most popular cron intervals because it provides regular updates without generating excessive load. It is frequently used for sending digest emails, generating periodic reports, and performing lightweight data backups. Each run has a generous 30-minute window to complete before the next execution. This expression is supported by standard cron on Linux/macOS, as well as cloud services like AWS CloudWatch, Google Cloud Scheduler, and GitHub Actions.
Use Case
Ideal for generating and caching sitemap files or RSS feeds for a content-heavy website that publishes articles throughout the day.
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Every 30 minutes
Next 10 Executions
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