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Cron Expression Generator

Build a five-field cron expression or explain one. Sunday is 0. Month and weekday names are not accepted.

What is Cron Expression Generator?

A cron expression generator builds or explains five fields: minute, hour, day of month, month, and day of week. Sunday is 0.

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Cron Expression Generator — Build or Explain Five Fields — Tools Star Hub

What this tool does

Build a five-field cron expression, or paste one and read a plain-language summary. The fields are minute, hour, day of month, month, and day of week. Sunday is 0. Names such as MON or JAN are not accepted, and a seconds field is not accepted.

How to use

  1. Choose Build and fill the five fields, or choose Explain and paste an expression.
  2. Press Build or Explain.
  3. Read the expression and the summary. Copy the expression if you want to keep it.

Examples

  • Every 15 minutes

    */15 * * * * means every 15 minutes.

  • Weekdays at 09:00

    0 9 * * 1-5 means at 09:00 on Monday through Friday. Sunday is 0.

Main features

  • Stars, single numbers, ranges, comma lists, and star steps such as */15.
  • A summary for common schedules, including every minute, hourly, daily, weekdays, and a monthly day.
  • A note when both the day of month and the day of week are restricted.

How it works

The five fields are minute, hour, day of month, month, and day of week. A star means every value in that field. */15 in the minute field means every 15 minutes. 1-5 in the day-of-week field means Monday through Friday. When both the day of month and the day of week are set to something other than a star, cron matches either day, not both.

Tips

  • Use the Timestamp Converter when you have a clock time and need a Unix timestamp, not a schedule.

Limitations

Five fields only. Names such as MON or JAN are rejected. A step inside a range, such as 0-30/10, is rejected. Day of week 7 is rejected. Sunday is 0.

See the disclaimer for what these tools do not cover.

FAQ

Is the Cron Expression Generator free?
Yes. You can build or explain a five-field expression here without paying or creating an account.
What if both the day of month and the day of week are set?
Cron matches either day, not both. 0 9 1 * 1 means 09:00 on the 1st of the month or on Monday. It does not mean only a Monday that falls on the 1st.
Why was MON or a six-field expression rejected?
This page uses numbers only, in five fields. Sunday is 0 and Saturday is 6. Day of week 7 is rejected. Names such as MON or JAN are rejected. A leading seconds field is not accepted. A step inside a range, such as 0-30/10, is rejected.
Is the expression sent to a server?
No. The expression and the summary are built in this browser tab. Tools Star Hub does not send that text to a server or save it in local storage.

Related tools

Helpful guides

Guide

How to Read a Cron Expression

Read a five-field cron expression. When both day fields are set, cron matches either day, not both.

Read guide