What are the five fields in a cron expression?

In order: minute (0-59), hour (0-23), day of the month (1-31), month (1-12), and day of the week (0-6, where 0 is Sunday). A cron expression is these five values separated by spaces, and a job runs whenever the current time matches all five.

What does the asterisk (*) mean?

An asterisk means 'every value is allowed' for that field — for example, an asterisk in the hour field means the schedule isn't restricted by hour at all, so it can trigger at any hour (subject to the other fields).

What's the difference between 'Every N' and 'Range'?

'Every N' (a step, shown as */N in the expression) means 'every Nth value starting from the field's minimum' — for example, */15 in the minute field means :00, :15, :30, :45. 'Range' means every value between two endpoints inclusive — for example, 9-17 in the hour field means every hour from 9am to 5pm.

What does 'Specific values' do?

It restricts the field to exactly the values you list, separated by commas — for example, entering 1,3,5 in the day-of-week field means the job only runs on Monday, Wednesday, and Friday.

Why does day of the week use numbers instead of names like MON or FRI?

Numeric values (0-6) are supported by every cron implementation, while 3-letter day/month names are a convenience some cron parsers support and others don't. This tool always outputs numbers so the expression works reliably wherever you paste it.

How is the plain-English description generated?

It's generated by parsing the assembled cron expression with a well-established, widely-used cron-description library — the same category of logic used across many developer tools — rather than a simplified custom guess, so the description accurately reflects what the expression actually does.

If two fields both restrict the day (day of month AND day of week), how do they combine?

Standard cron treats day-of-month and day-of-week as an OR when both are restricted (not set to *) — the job runs if either condition matches. If only one of the two is restricted, only that one applies.

Is my schedule configuration uploaded anywhere?

No. The entire builder, expression assembly, and description all run locally in your browser using JavaScript. No network request is made, and nothing you configure is stored or transmitted.

Cron Expression Generator — Build & Understand Cron Schedules

Our Cron Expression Generator lets you build a valid cron schedule without memorizing cron syntax. Set each of the five fields — minute, hour, day of month, month, and day of week — to 'every', a step, a range, or specific values, and the tool assembles the expression live while showing a plain-English description of exactly when it will run (powered by the same parsing logic used across countless developer tools). A reference table explains each field's valid range, and a set of common examples can be loaded into the builder with one click. Nothing is uploaded — everything runs instantly in your browser.

Quick Answer

A Cron Expression Generator lets you build a valid cron schedule using simple field-by-field controls instead of memorizing cron syntax, showing the resulting expression and a plain-English description of when it will run. Free, and everything runs instantly in your browser — nothing is uploaded.

* * * * *

Every minute

Minute

Hour

Day of month

Month

Day of week

The cron expression is made of five fields. Each field can have the following values.

*	*	*	*	*
minute (0-59)	hour (0-23)	day of the month (1-31)	month (1-12)	day of the week (0-6)

Here are some examples for you.

Cron expression	Schedule
* * * * *	Every minute
/10 * * *	Every 10 minutes
0 * * * *	Every hour
0 0 * * *	Every day at 12:00 AM
0 9 * * 1-5	Every weekday at 9:00 AM
0 0 * * 5	At 12:00 AM, only on Friday
0 0 1 * *	At 12:00 AM, on day 1 of the month

How to Use the Cron Expression Generator

1
Set the mode for each field (Minute, Hour, Day of Month, Month, Day of Week) to Every, Every N, Range, or Specific values.
2
Fill in the value(s) for any field not set to 'Every' — the expression and its plain-English description update instantly.
3
Check the reference table if you're unsure what range of values a field accepts.
4
Click any row in the examples table to load that common schedule straight into the builder.
5
Click 'Copy' to copy the finished cron expression.

Why Use Cron Expression Generator?

Cron expressions power scheduled tasks across nearly every corner of software infrastructure — crontab on Linux servers, GitHub Actions workflow triggers, Kubernetes CronJobs, CI/CD pipelines, and countless SaaS scheduling features all use the same five-field syntax. The syntax is compact and powerful, but that compactness is exactly what makes it easy to get wrong: is */15 in the hour field 'every 15 hours' or did you mean the minute field? Does '5' in the day-of-week field mean Friday or Thursday? A misconfigured cron expression can silently run a job at the wrong time, or not at all, and the mistake often isn't caught until someone notices a job didn't run when expected. This tool removes the guesswork: build your schedule field by field using plain controls instead of memorized syntax, and see the exact plain-English meaning of the resulting expression before you paste it into a crontab file or workflow config. The description generator uses well-tested, widely-used parsing logic so its explanations are as accurate as the cron syntax itself, not a rough approximation.

Frequently Asked Questions

Related Tools

Regex Tester — Free Online Regular Expression Tool

Test regular expressions against sample text with live match highlighting, capture groups, and flag support (g, i, m, s, u). Free, no signup, runs entirely in your browser.

Timestamp Converter — Unix Epoch to Date & Back

Convert Unix timestamps (seconds or milliseconds) to human-readable dates, or convert any date back to an epoch timestamp. Shows local time and UTC. Free, runs in your browser.