Cron Expression Generator
Runs entirely in your browser
Build a 5-field cron expression from simple inputs, or paste one to get a plain-English description.
Edit the fields below, or paste your own expression here.
Every 15 minutes.
What is a Cron Expression?
A cron expression is a compact way to describe a recurring schedule, made of five fields — minute, hour, day of month, month, and day of week — used by Unix cron, CI pipelines and job schedulers to decide when a task should run.
How to use Cron Expression Generator
- Edit the Minute, Hour, Day of month, Month and Day of week fields, or type a full expression directly.
- Read the generated plain-English description to confirm it matches what you intended.
- Copy the expression or description for use elsewhere.
Features
- Two-way sync — edit individual fields or the full expression.
- Plain-English description for common patterns (*, */n, ranges, lists).
- Validates each field and reports which one is invalid.
- 100% client-side — nothing is sent to a server.
Example
0 9 * * 1-5 — At 09:00, Monday through Friday.
0 0 1 * * — At 00:00, on day 1 of the month.
*/15 * * * * — Every 15 minutes.
Tips
- If both the day-of-month and day-of-week fields are set to something other than
*, standard cron runs the job when either condition matches, not only when both match — even though this tool's description lists them together as "on day X, on day Y". - This tool accepts day-of-week values 0–6 only, with 0 meaning Sunday. Some cron implementations also accept 7 as an alternate value for Sunday — that will be rejected here as invalid.
- A step can be combined with a range, like
1-10/2in the minute field (minutes 1, 3, 5, 7, 9) — this isn't the same as a bare step like*/2, which starts counting from the field's minimum value. - If you need seconds-level precision (used by schedulers like Quartz), this tool won't generate that sixth field — you'd need to add it manually in the target system's own syntax.
Is Cron Expression Generator safe?
Yes. Cron Expression Generator parses each of the five fields and builds the plain-English description with local JavaScript logic in your browser, so the expression you build or paste is never sent to a server.
Frequently Asked Questions
What do the five cron fields mean?
In order: minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-6, where 0 is Sunday). Each field accepts *, a number, a range like 1-5, a list like 1,3,5, or a step like */15.
Does this support seconds-level cron?
No. This tool generates the standard 5-field cron format used by Unix cron, most CI systems and job schedulers. Some tools (like Quartz) add a seconds field, which isn't covered here.
Will the description cover every possible expression?
It covers the common patterns — exact values, *, */n steps, ranges and comma lists — but very unusual combinations may fall back to a more literal, field-by-field description.