Development
Cron Generator
Build cron expressions by clicking or type them in – the tool explains them in plain English, shows the next ten runs, warns about typical mistakes and provides the ready-made crontab line.
- Runs entirely in your browser
- No data upload
- No sign-up
- Free
Set minute
Next runs
Ready-made crontab line
Add it with crontab -e on the server – or in your hosting provider’s cron job section (there, usually just the expression and the command separately).
Guide
How it works
- Enter an expression or choose a template
Type a cron expression, paste an existing one or start with a template such as “Daily at 03:30”.
- Set the fields
Click minute, hour, day, month or weekday and choose: every, an interval, specific values or a range. The expression adjusts instantly – and vice versa.
- Check
The plain-English description and the next ten runs show whether the schedule is right. Notes warn about typical pitfalls, such as a * in the minute field.
- Add it
Enter the command and copy the finished line – for crontab -e on the server or for your hosting provider’s cron job section.
FAQ
Frequently asked questions
How is a cron expression structured?
It has five fields separated by spaces: minute (0–59), hour (0–23), day of month (1–31), month (1–12 or JAN–DEC) and weekday (0–7 or SUN–SAT, 0 and 7 are Sunday). So “30 3 * * *” means: every day at 03:30.
What do * , - and / mean?
* stands for “every value”, the comma separates a list (1,15), the hyphen a range (1-5) and the slash an interval: */15 in the minute field means “every 15 minutes”, 9-17/2 in the hour field “every two hours from 9 to 17”.
Why does my job run too often when I specify day and weekday?
A peculiarity of cron: if day of month and weekday are both set, the job runs when either of them matches. So “0 0 13 * 5” runs on every 13th and additionally on every Friday – not only on Friday the 13th.
In which time zone do cron jobs run?
In the server’s time zone – often UTC. The preview here uses your browser’s time zone. If the server differs, the times shift accordingly; if in doubt, check with your hosting provider.
Can I use seconds or characters such as L, W and ??
Not in classic crontab. These extensions and a sixth field for seconds only exist in libraries such as Quartz or Spring. The tool detects such expressions and points this out.
Is my command stored?
No. Everything happens locally in your browser.