About this tool
A cron expression packs a whole schedule into five short fields, which makes it easy to get wrong and hard to read back later. This explainer turns an expression such as */15 9-17 * * 1-5 into a plain English sentence, then lists what every field means so you can see exactly where the schedule comes from.
It also calculates the next five times the schedule will fire, shown in your local time zone or in UTC, which is the quickest way to catch a mistake before a job reaches a server. Everything is calculated in your browser, and macros like @daily and an optional leading seconds field are understood.
How to use the Cron Explainer
- 1Type a cron expression into the input, or click a preset such as Weekdays at 9:00.
- 2Read the plain English description shown above the field table.
- 3Check the table to see what the minute, hour, day and month fields each mean.
- 4Compare the next five run times, and switch between your time zone and UTC.
- 5Turn on 24-hour time if you prefer it, then copy the description.
Features
Plain English output
Get a readable sentence such as Every 15 minutes, between 09:00 AM and 05:59 PM, Monday through Friday.
Field-by-field table
See each field's value next to a short meaning, including ranges, steps, lists and month or weekday names.
Next five runs
Calculate upcoming run times from the current moment, in your local time zone or in UTC.
Macros and seconds
Use @hourly, @daily, @weekly, @monthly or @yearly, or add a leading sixth field for seconds.
Eight presets
Start from common schedules like every five minutes, weekdays at 9:00 or the first day of the month.
Frequently asked questions
What order are the cron fields in?
Minute, hour, day of month, month and day of week. When six fields are given, the first one is read as seconds.
Why does day of week 0 mean Sunday?
Cron counts weekdays starting from Sunday as 0, and many systems also accept 7 for Sunday. Three-letter names such as MON or FRI work as well.
Which time zone are the next run times in?
Your browser's local time zone by default, with the zone name displayed. Turn on Show UTC to see the same runs in UTC, which is what most servers use.
Does this work for Quartz or AWS schedules?
It reads standard cron syntax with an optional seconds field. Quartz extras such as a year field, and the extra rules some cloud schedulers add, are not supported.
Is my cron expression sent anywhere?
No. The description and run times are calculated in the page, and nothing is stored after you close the tab.