What Is the Cron Expression Parser?

Cron expressions are used in crontabs, CI pipelines, and job schedulers to define when a job runs. An expression like 0 9 * * 1-5 is hard to read at a glance; it is not obvious when it will actually run.

This tool turns the expression into a description such as "weekdays at 09:00" and shows the next run times. For 0 0 1 * *, it shows "day 1 of every month at 00:00." The field breakdown also shows how each part expands. That makes it easier to check day-of-month and day-of-week settings before adding the expression to a schedule.

How to Use

1. Enter the cron expression you want to check.
2. The description and the next five run times appear.
3. Check the parsed fields to see how each part is expanded.

Starting from a common expression saves you from typing it out.

Supported Formats

The tool supports the standard five-field format (minute hour day month weekday). Values can be listed with commas, and ranges can be combined with steps (for example, 0 9-17/2 * * *).

Each field accepts the following values.

Month and weekday names are case-insensitive.

Use Cases

• Checking that a cron expression runs on the intended days and times before adding it to a crontab or CI schedule
• Confirming that a combined day-of-month and day-of-week expression does not run on more days than expected
• Reviewing cron expressions with your team and checking the description alongside the next run times
• Checking whether month-end or leap-year settings produce the dates you expect

Things to Keep in Mind

• Only the five-field format is supported; expressions with a seconds field are not.
• When both day of month and day of week are set, a run happens on a day that matches either condition.
• Times use your browser's local time zone. Results can differ if the server uses another time zone.
• Upcoming runs are calculated up to five years ahead. If an expression has no run within five years, the tool says so.