Compose and read a five-field cron expression

Compose and read a five-field cron expression. Handy for teams and individuals planning schedules, checking deadlines or preparing a document.

Compose and read a five-field cron expression. See a clear result update immediately in your browser, with no account, upload or stored data to worry about.

How to use

Find the single input box where the expression goes: five values separated by spaces, in the order minute, hour, day of the month, month and day of the week.
Type your expression or paste one copied from a configuration file, and leave the rest of the field empty.
Run the analysis: each field is split apart and the tool writes a plain sentence describing the schedule.
Read that sentence carefully and adjust the expression if the timing it describes is not the one you meant to set up.
Clear the box before trying another expression so the two tests do not get mixed up in the same reading.

Example

The sample puts 30 in the minute field, 4 in the hour field and 1 in the day-of-month, month and weekday fields. After the analysis, read the generated sentence: it tells you when the job would run and how the date constraints are combined.

Input

30 4 1 1 1

Limits and formats

This is a reading tool: it explains an existing expression, it does not schedule anything and it never touches files on your computer.
The classic five-field layout is covered here, so variants that add a seconds field sit outside what this page describes.
Some schedulers treat day-of-month and day-of-week as alternatives, others as a requirement; confirm how your own system behaves before relying on a written expression.
A valid expression can still fire at an odd moment around month ends or clock changes, so check it against a real date.

Where processing happens

The whole analysis happens in your browser. The expression you type stays on your device, nothing is transmitted and no copy survives once you close the tab, so expressions taken from private files can be tested safely.

Frequently asked questions

What do the five fields of an expression stand for?

They describe, in order, the minute, the hour, the day of the month, the month and the day of the week. A field can hold a single value, a range, a list or a step, which is what lets one expression cover a daily job as well as a monthly one.

How can I tell whether my expression runs once a day?

It runs once a day only when the minute and the hour are fixed while the date fields stay wide open. Read the sentence the tool produces and check that no extra day constraint has been added by the fields you typed.

Does this page run the job for me?

No. It only reads the expression and rewrites it as a sentence you can verify. Nothing is launched and no command is executed, so you still have to copy the expression into your own scheduler or hosting panel.