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Cron Expression Tester

Parse and test cron expressions, see them explained in plain English, and view upcoming run times in any timezone

5 fields: minute hour day-of-month month day-of-week. Supports *, ,, -, /, month/day names, and @hourly, @daily, etc.

*/15
Minute
0-59
9-17
Hour
0-23
*
Day (Month)
1-31
*
Month
1-12
1-5
Day (Week)
0-6 (Sun=0)

Plain English

Every 15 minutes from 09:00 through 17:59 on Monday through Friday

Next 7 Runs

  1. #1Mon, Jul 20, 2026, 09:00in 2 days
  2. #2Mon, Jul 20, 2026, 09:15in 2 days
  3. #3Mon, Jul 20, 2026, 09:30in 2 days
  4. #4Mon, Jul 20, 2026, 09:45in 2 days
  5. #5Mon, Jul 20, 2026, 10:00in 2 days
  6. #6Mon, Jul 20, 2026, 10:15in 2 days
  7. #7Mon, Jul 20, 2026, 10:30in 2 days
Syntax Reference

* — every value

a,b,c — list of specific values

a-b — range from a through b

*/n — every n values

a-b/n — every n in range a-b

JAN-DEC — month names accepted

SUN-SAT — weekday names (SUN=0, SAT=6)

Macros: @hourly, @daily, @weekly, @monthly, @yearly, @midnight

Note: when both day-of-month and day-of-week are restricted, a day matches if either matches (POSIX behavior).

Guide

About this cron expression tester

The cron tester parses traditional five-field cron expressions, explains the schedule in plain English, and calculates the next seven run times in a selected timezone. It supports lists, ranges, steps, month and weekday names, and common macros such as @daily.

How to use the cron expression tester

  1. 1.Enter a five-field expression in minute, hour, day-of-month, month, and day-of-week order.
  2. 2.Choose the timezone used to preview the schedule.
  3. 3.Review each parsed field, the plain-language explanation, and the upcoming run times.

Important details

Cron implementations differ

This tester uses the common five-field format. Quartz, AWS EventBridge, Kubernetes, systemd timers, and vendor schedulers may use a seconds or year field, different weekday numbering, or special characters that this parser does not support.

Timezone and daylight-saving behavior

A local wall-clock time may occur twice or not at all during a daylight-saving transition. Confirm the scheduler’s configured timezone and DST behavior before relying on a production schedule.

Frequently asked questions

Does this tester run a job?

No. It parses and previews a schedule only; it does not register or execute tasks.

Why does my six-field cron expression fail?

This parser expects five fields and does not include a leading seconds field. Remove it only if the target scheduler also uses five-field cron syntax.