Cron expressions look like secret code, but they are just five small fields that tell a computer when to run a job. This free cron expression explainer turns that code into plain words, so you can check a schedule before you trust it with real work.
The five fields, in order, are minute, hour, day of month, month, and day of week. So 30 8 * * 1-5 means: at minute 30, at hour 8, on any day of the month, in any month, on weekdays Monday to Friday. In short, weekdays at 8:30 in the morning.
Each field accepts a few handy patterns. A star means every value. A slash means a step, so */15 in the minute field means every 15 minutes. A dash means a range, like 1-5 for Monday to Friday. A comma means a list, like 1,15 for the 1st and 15th of the month.
You can also write month and weekday names in English: JAN to DEC and SUN to SAT. That often reads better than numbers, especially for a schedule like 0 0 1 JAN * which runs once a year, on the 1st of January at midnight.
Paste any expression in the box and press Explain. The tool breaks down each field, then shows the next three run times from this moment. If the next runs surprise you, the schedule is probably not what you meant, and it is far better to learn that here than after a missed backup.
Two classic mistakes are worth knowing. First, day of month and day of week combine in a special way: when both are limited, the job runs when either one matches, not both. Second, servers often run on UTC time, not your local time, so a job set for 8:00 may really run at 10:00 in your city. Always check the timezone of the machine that runs the job.
Try the example already in the box, then paste a schedule from your own server or hosting panel. It is free, needs no sign-up, and everything runs in your browser.
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