Free tool · runs in your browser
Cron expression editor
Type or build a cron schedule and read it in plain English, with the next run times in any time zone. Works with Linux crontab, Quartz, AWS EventBridge and GitHub Actions.
Next runs
Next 6 weeks
Builder
Change a field and the expression updates.Use it
Examples
Click one to load it. Examples the selected dialect can't express are hidden.Minutes and hours
Days
Months
Seconds
Quartz and AWS only
Reference
| Field | Allowed values | Special characters |
|---|
Stays on your device
Descriptions and run times are calculated in your browser. Nothing is uploaded. Your last expression, dialect and time zone are kept in this browser; a share link keeps them in the part of the URL after #.
Day fields: OR, not AND
In standard cron, if both day-of-month and day-of-week are restricted, the job runs when either matches. 0 0 13 * 5 runs on every 13th and on every Friday, not only on Friday the 13th.
Daylight saving time
Times that fall in a clock change are flagged: a skipped time (spring forward) or a repeated one (fall back). Cron implementations handle these differently, so check yours, or schedule in UTC.
Check your platform
The rules here follow each platform's documented syntax. Versions and forks differ in small ways, so test important schedules where they will run.
Questions
What do the five fields of a cron expression mean?
In order: minute (0–59), hour (0–23), day of the month (1–31), month (1–12 or JAN–DEC) and day of the week (0–7 or SUN–SAT, where 0 and 7 are both Sunday). An asterisk means every value; for example 30 9 * * 1-5 runs at 09:30 Monday to Friday.
Why does my job run on more days than I expected?
In standard cron, if both the day-of-month and day-of-week fields are restricted, the job runs when either one matches, not both. 0 0 1 * MON runs on the 1st of every month and also every Monday. The description here spells this out.
Which time zone do cron jobs use?
It depends on the system. Linux crontab uses the server's local time zone, GitHub Actions schedules always use UTC, and Kubernetes CronJobs use the controller's time zone unless you set spec.timeZone. Pick the time zone here to see the next runs as that system will.
What is the difference between crontab, Quartz and AWS cron?
Quartz adds a seconds field in front and an optional year at the end; AWS EventBridge adds a year at the end. Both number weekdays 1–7 starting with Sunday, need ? in either the day-of-month or day-of-week field, and support L, W and #. Use the dialect switch to check an expression for each.
Is anything uploaded?
No. Parsing, descriptions and next run times are calculated in your browser. Nothing is sent to a server, and a share link keeps the expression in the part of the URL after #.