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Crontab cron expression: every 12 hours
To run a Crontab job every 12 hours, use:
0 0,12 * * *At minute 0, during hours 00, 12.
Your week at a glance
Upcoming runs
| # | Local | UTC | From now |
|---|
Copy-ready code
Why use this schedule
Twice a day, at midnight and noon. Written as a list, which is clearer than */12.
- Twice-daily database dumps
- Syncing a catalogue to a marketplace
- Morning and evening digest emails
First runs, as an example
Starting from 1 January 2027, evaluated in UTC:
| # | Date and time (UTC) |
|---|---|
| 1 | Fri, 01 Jan 2027, 00:00:00 |
| 2 | Fri, 01 Jan 2027, 12:00:00 |
| 3 | Sat, 02 Jan 2027, 00:00:00 |
| 4 | Sat, 02 Jan 2027, 12:00:00 |
| 5 | Sun, 03 Jan 2027, 00:00:00 |
| 6 | Sun, 03 Jan 2027, 12:00:00 |
Every 12 hours in every dialect
| System | Expression |
|---|---|
| Crontab (this page) | 0 0,12 * * * |
| Quartz | 0 0 0,12 * * ? |
| Spring | 0 0 0,12 * * * |
| Kubernetes | 0 0,12 * * * |
| AWS EventBridge | 0 0,12 * * ? * |
| Jenkins | H 0,12 * * * |
| GitHub Actions | 0 0,12 * * * |
| node-cron | 0 0,12 * * * |
| Apache Airflow | 0 0,12 * * * |
| Azure Functions | 0 0 0,12 * * * |
| Google Cloud Scheduler | 0 0,12 * * * |
Need to translate a different expression? Use the cron converter.
Ready-to-use Crontab config
Drop this into your project. The expression is the one above.
0 0,12 * * * /path/to/command >> /var/log/job.log 2>&1The Crontab fields, in order: minute (0-59), hour (0-23), day-of-month (1-31), month (1-12), day-of-week (0-7, 0 and 7 = Sunday).
Things to watch out for in Crontab
- Fields are minute, hour, day-of-month, month, day-of-week. There is no seconds field, so one minute is the finest resolution.
- Cron runs in the server's local time zone. Check it with the date command, or put CRON_TZ=Asia/Kolkata above the line on cronie-based systems.
The common mistake with this schedule
In UTC, midnight and noon fall at odd local times. For India, 00:00 and 12:00 UTC are 05:30 and 17:30 IST.
Frequently asked questions
How do I run a Crontab job every 12 hours?
Use 0 0,12 * * *. At minute 0, during hours 00, 12.
What is the every 12 hours cron expression in other systems?
Quartz: 0 0 0,12 * * ?; Spring: 0 0 0,12 * * *; Kubernetes: 0 0,12 * * *. The table on this page lists every dialect.
Which time zone does Crontab use for this schedule?
Cron runs in the server's local time zone. Check it with the date command, or put CRON_TZ=Asia/Kolkata above the line on cronie-based systems.