How do cron schedules work?

A cron expression is a set of fields — minute, hour, day, month and day-of-week (or six fields with seconds). The builder labels each field, reads the whole expression back in plain English, and lists the next ten run times in a timezone you choose.

What are the @macros?

Shorthand tokens like @reboot (run at startup), @daily, @weekly and @yearly. The builder includes them alongside the standard field syntax.

Does it tell me when the job will run next?

Yes — it previews the next ten run times in your selected timezone, all computed locally.

Cron Expression Builder

Compose a cron schedule, read it back in plain English and preview the next run times. Everything is parsed on your device — your expressions never leave the browser.

Runs in your browser — nothing is uploaded

Presets

Cron expression

Valid

Seconds

Five fields — minute hour day-of-month month day-of-week — or six with a leading seconds field. Supports *, */n, a-b, a,b,c, ranges with steps, names (JAN–DEC, SUN–SAT) and macros like @daily or @reboot.

Fields

Minuteevery 5 minutesHourevery hourDay of monthevery day of the monthMonthevery monthDay of weekevery day of the week

Description

Every 5 minutes

Next 10 runs

DST approximated

This schedule has no upcoming occurrences in the next six years.

What Cron Expression Builder does

Five or six field expressions plus @macros, including @reboot
Human-readable description of the schedule, per field and overall
Next 10 run times in a timezone you choose
Build from labelled fields, presets, or a random expression
Validation for malformed expressions

How to use it

01
Open the Cron builder.
02
Type an expression or build one from the labelled fields.
03
Read the plain-English description and the next run times.
04
Copy the expression.

Common questions

How do cron schedules work?: A cron expression is a set of fields — minute, hour, day, month and day-of-week (or six fields with seconds). The builder labels each field, reads the whole expression back in plain English, and lists the next ten run times in a timezone you choose.
What are the @macros?: Shorthand tokens like @reboot (run at startup), @daily, @weekly and @yearly. The builder includes them alongside the standard field syntax.
Does it tell me when the job will run next?: Yes — it previews the next ten run times in your selected timezone, all computed locally.

More tools

ReadyJSON Formatter & ValidatorFormat, validate, minify and sort JSON — instantly, in your browser.Runs in your browserOpen ReadySQL FormatterPretty-print and tidy SQL across 15+ dialects.Runs in your browserOpen ReadyRegEx TesterTest, explain and generate code for regular expressions.Runs in your browserOpen