What is a cron expression?

A cron expression is a compact string of five fields — minute, hour, day of month, month, and day of week — that defines a recurring schedule. It is the standard way to tell Linux, CI systems and job schedulers when to run a task automatically.

How do I read the five cron fields?

From left to right the fields are minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-6, where 0 is Sunday). An asterisk in any field means 'every' value for that field.

What does */5 mean in a cron expression?

The slash introduces a step value. */5 in the minute field means 'every 5 minutes'. Similarly */2 in the hour field means 'every 2 hours'. It is the standard way to express regular intervals.

Can this tool explain a schedule in plain English?

Yes. As you build the expression, the tool shows a human-readable description such as 'At 09:00 every Monday', so you can confirm the schedule does exactly what you intend before deploying it.

Where can I use the generated cron expression?

The five-field expression works in Linux and macOS crontab, most CI/CD systems like GitHub Actions and GitLab, container schedulers, and countless job-scheduling libraries and frameworks that follow the standard cron syntax.

Why do my cron jobs sometimes not run?

Common causes include the crontab using a different timezone than you expect, environment variables and PATH not being set inside cron, or a subtle field mistake. Generating the expression here removes the syntax errors, leaving only environment issues to check.

Cron Expression Generator

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Schedule

0 9 * * *

"At 09:00 every day"

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Cron Expression Generator — Build Correct Schedules Without the Guesswork

Cron is the backbone of automated scheduling on Linux and in countless CI/CD and job systems, but its terse five-field syntax is notoriously easy to get wrong. A single misplaced value can mean a backup that never runs, a report that fires a hundred times, or a job that silently waits for a day that never comes. This free generator removes that risk entirely: you choose a schedule from simple options, and it produces a correct cron expression alongside a plain-English description so you can confirm exactly what it will do before you deploy it. No signup, no syntax memorization, no failed jobs.

Understanding the Five Fields

Every standard cron expression is five fields separated by spaces, read left to right:

Position	Field	Allowed values
1	Minute	0-59
2	Hour	0-23 (24-hour clock)
3	Day of month	1-31
4	Month	1-12
5	Day of week	0-6 (0 = Sunday)

So 0 9 * * 1 reads as: minute 0, hour 9, every day of the month, every month, on day-of-week 1 — in other words, "at 09:00 every Monday." Once you internalize the field order, the rest is a matter of the special characters.

The Special Characters That Do the Heavy Lifting

Asterisk (*) means "every" value for that field. * * * * * runs every single minute.
Slash (/) defines steps. */15 in the minute field means "every 15 minutes." */2 in the hour field means "every 2 hours."
Comma (,) lists specific values. 0,30 in minutes means "at :00 and :30." 1,3,5 in day-of-week means Monday, Wednesday and Friday.
Hyphen (-) defines a range. 1-5 in day-of-week means Monday through Friday.

Combining these gives enormous flexibility. 0 9-17 * * 1-5 runs at the top of every hour from 9am to 5pm on weekdays — a common pattern for business-hours tasks. This generator lets you build such schedules through simple choices and shows the resulting expression, so you learn the syntax by seeing it produced correctly.

Common Schedules You Will Reach For

Expression	Meaning
* * * * *	Every minute
/5 * * *	Every 5 minutes
0 * * * *	Every hour, on the hour
0 9 * * *	Every day at 09:00
0 9 * * 1	Every Monday at 09:00
0 0 1 * *	First day of every month at midnight
0 2 * * 0	Every Sunday at 02:00 (a classic backup window)

Why Cron Jobs Fail — and How This Helps

The single most common cause of cron frustration is a syntax mistake, and that is exactly what this tool eliminates: the expression it outputs is always structurally valid. But it is worth knowing the other pitfalls too. Cron runs in the server's timezone, which may not be your local time — a job set for "9am" could fire at 9am UTC, hours away from your expectation. Cron also runs with a minimal environment, so scripts that rely on variables or a full PATH available in your interactive shell may fail silently; specifying absolute paths and setting needed variables inside the job solves this. Finally, remember that day-of-month and day-of-week interact: when both are restricted, most cron implementations run the job when either matches, which can cause a schedule to fire more often than intended. By generating a correct expression and reading the plain-English summary, you remove the syntax variable entirely, leaving only these environment factors to verify.

Where These Expressions Work

The five-field format this tool generates is the widely supported standard. It works directly in Linux and macOS crontab, in the scheduled-workflow triggers of GitHub Actions and GitLab CI, in Kubernetes CronJobs, and in the many scheduling libraries across languages that follow cron syntax. Some systems add a sixth field for seconds or support special strings like @daily, but the classic five-field expression remains the most portable and universally understood, which is why this generator focuses on producing it cleanly.

Build It, Read It, Trust It

The real value of generating a cron expression rather than hand-writing one is confidence. You see the schedule described in words — "At 02:00 on day 1 of every month" — and know it matches your intent before a single job runs. That confidence is worth a great deal when the task is a nightly backup, a billing run, or a data sync where a missed or duplicated execution has real consequences. Build your schedule, confirm the description, copy the expression, and deploy it knowing the syntax is correct. It is free, unlimited, and runs entirely in your browser, alongside our other developer tools for formatting, converting and generating the building blocks of your projects.