Cron Generator
Free online cron expression generator and explainer. Build cron schedules visually or paste an expression to get a plain-English explanation with next run times. No signup required.
How to Use the Cron Generator
Use the builder on the left to set your schedule visually — configure minute, hour, day, month, and weekday fields using radio buttons, checkboxes, and quick-select presets. The cron expression updates in real time as you make changes. Alternatively, type or paste an existing expression into the expression bar to see it explained in plain English and view the next 10 scheduled run times. Use the Presets dropdown for common schedules like “every 5 minutes” or “weekdays at 9 AM.” Click Share to generate a permalink with your expression encoded in the URL.
About This Tool
A visual cron expression builder and explainer that runs entirely in your browser. Build complex schedules using intuitive controls — checkboxes for specific minutes, pill toggles for weekdays, radio buttons for intervals — and see the resulting cron expression update instantly. Paste any standard 5-field Unix cron expression to get a plain-English explanation powered by cronstrue, a field-by-field breakdown table, and the next 10 scheduled run times in your chosen timezone. Supports special strings like @daily, @weekly, and @reboot. Warns about common pitfalls like the day-of-month / day-of-week OR behavior and impossible date combinations. Zero server communication — your data never leaves your device. Related: Regex Tester for testing regular expressions, Date Calculator for date arithmetic.
Quick Reference Table
| Symbol | Meaning | Example |
|---|---|---|
| * | Every value | * (minute) — every minute |
| */n | Every n values | */15 — every 15 minutes |
| n | Specific value | 30 — at minute 30 |
| n,m | List | 0,30 — at minute 0 and 30 |
| n-m | Range | 9-17 — hours 9 through 17 |
| n-m/s | Range with step | 0-59/10 — every 10 minutes |
| SUN–SAT | Day names | MON-FRI — weekdays |
| JAN–DEC | Month names | JAN,APR,JUL,OCT — quarterly |
Frequently Asked Questions
What does '*/15 * * * *' mean?
This runs every 15 minutes — at minute 0, 15, 30, and 45 of every hour, every day. The */ syntax means ‘every nth value’ — */15 divides the 0–59 minute range into steps of 15.
Why does my job run when I didn’t expect it?
The most common surprise is the OR behavior when both day-of-month and day-of-week are non-wildcards. Most cron implementations fire when either condition is true, not both. Use * for one of the fields if you need strict AND behavior.
What timezone does cron use?
By default, cron on Linux systems uses the server’s local timezone, which is often UTC on cloud servers. GitHub Actions always runs in UTC. AWS EventBridge uses UTC. Always confirm your platform’s timezone and account for daylight saving time.
Can I schedule a job for the last day of the month?
Standard cron has no direct way to express ‘last day of month’ since months have different lengths. Some platforms support the L symbol. Alternatively, schedule for day 28 and add a date check in your script.
Is my data sent to a server?
No. All expression parsing, explanation, and run-time calculation happens entirely in your browser. Your data never leaves your device.