Cron Expression Generator

Builds cron expressions from plain choices such as “every weekday at 9:30” and writes them for crontab, Kubernetes, GitHub Actions, AWS and Quartz.

Pick a schedule in plain words, no cron syntax needed

Shows the next runs so you can check it

Ready-made formats for AWS EventBridge, Quartz and GitHub Actions

Your schedule stays on this device

This tool runs entirely inside your web browser. Your schedule is processed on your own device and is never sent to our servers. How this works

Copy it for where it will run

Linux crontab

0 9 * * 1-5 /path/to/command

Runs in the server’s local time zone. Replace the command path with your own.

Kubernetes CronJob

schedule: "0 9 * * 1-5"

Uses the controller’s time zone unless you set spec.timeZone (e.g. "Europe/London").

GitHub Actions

on:
  schedule:
    - cron: '0 9 * * 1-5'

Always runs in UTC, and may start a few minutes late when GitHub is busy.

AWS EventBridge

cron(0 9 ? * MON-FRI *)

Six fields with a year at the end; runs in UTC unless the schedule has a time zone.

Quartz / Spring

0 0 9 ? * MON-FRI

Seconds come first. Works in Quartz and in Spring’s @Scheduled(cron = "…").

Cron Expression Generator is a free tool that writes cron schedules for you. Choose how often a job should run in plain words, such as every 15 minutes, every weekday at 09:30 or on the 1st of every month, and get the cron expression, a plain-English description and the next run times. It also writes the schedule in the exact format needed by crontab, Kubernetes, GitHub Actions, AWS EventBridge and Quartz. It runs entirely in your browser.

How to build a cron expression

Choose how often the job runs: every few minutes or hours, every day, on certain days of the week, monthly or yearly.
Set the time and days. The expression updates as you go.
Check the description and next run times, then copy the version for the system you use.

For anything the presets don’t cover, choose Advanced and edit each field directly.

Common schedules

*/5 * * * *: every 5 minutes
0 * * * *: every hour, on the hour
0 0 * * *: every day at midnight
30 9 * * 1-5: weekdays at 09:30
0 18 * * 5: Fridays at 18:00
0 3 1 * *: 03:00 on the 1st of every month
0 0 1 1 *: once a year, at midnight on 1 January

One schedule, different systems

Linux crontab and Kubernetes use the standard five fields.
GitHub Actions uses the standard format too, but always in UTC.
AWS EventBridge wraps it as cron(…), adds a year field, and requires ? in either the day-of-month or the day-of-week field.
Quartz and Spring put a seconds field first and also use ?.

Mixing these up is one of the most common reasons a scheduled job never runs, so the generator writes each version for you, using day names such as MON-FRI where numbering differs between systems.

Tips

Pick an odd minute such as 7 or 43 for heavy jobs, so they don’t all start at exactly the top of the hour with everyone else’s.
Jobs set for 01:00–03:00 may be skipped or run twice when clocks change for daylight saving time, unless the server runs in UTC.
To understand an existing expression, paste it into the Cron Parser, which explains it and shows its next runs in any time zone.

Frequently asked questions

What is a cron expression?

A short line of five fields (minute, hour, day of month, month and day of week) that tells a scheduler when to run a job. For example, 30 9 * * 1-5 means 09:30 every weekday.

Why are there different formats for AWS and Quartz?

Schedulers extend standard cron differently. AWS EventBridge adds a year field and needs “?” in either the day-of-month or day-of-week field; Quartz and Spring add a seconds field at the start. The generator writes the same schedule correctly for each.

Which time zone will my job run in?

It depends on where it runs: Linux crontab uses the server’s time zone, GitHub Actions always uses UTC, and AWS uses UTC unless your schedule sets a time zone. The next-run list assumes UTC, like most servers; check other zones with the Cron Parser.

Can I run a job on the last day of the month?

Standard cron can’t express “last day”. A common workaround is to run on days 28–31 and have the job check whether tomorrow is the 1st. Quartz and AWS support L for “last”.

Is anything sent to a server?

No. Expressions are built and checked in your browser.

Last updated 27 September 2026