Cron Expression Explainer
Paste a cron expression and read what it actually does.
Cron Expression Explainer
Developer tool running locally in browser
What does Cron Expression Explainer do?
Translate a cron expression into plain English and see the next run times. The fastest way to check whether an inherited schedule does what the comment above it claims.
How to Use Cron Expression Explainer
- 1Paste the expressionFive or six space-separated fields.
- 2Read the descriptionIn plain English, with a field breakdown.
- 3Check the next runsConfirm the schedule matches the intent.
Key Features
- Plain-English description of any cron expression
- Next ten run times listed with dates
- Standard 5-field, 6-field with seconds and Quartz syntax
- Field-by-field breakdown showing what each part matches
- Clear error when the expression is invalid
Frequently Asked Questions
What does "0 2 * * *" mean?
At 02:00 every day. Minute 0, hour 2, every day of the month, every month, every day of the week.
What is the difference between */5 and 0/5?
Nothing in practice — both mean every fifth value starting from zero. */5 is standard cron syntax; 0/5 is Quartz syntax. Some parsers accept only one, so match your scheduler.
Why has my cron job not run?
Common causes: a day-of-month and day-of-week combination that ORs unexpectedly, a time zone difference between where you tested and where it runs, or a daylight saving transition skipping the hour.
Does it support named months and weekdays?
Yes. JAN through DEC and SUN through SAT are recognised, along with the @daily, @hourly, @weekly, @monthly and @yearly shorthands.
Input is processed in your browser and never transmitted. That said, treat any web page as untrusted for live production secrets — rotate anything you paste anywhere.
Related Tools
Cron Expression Generator
Build a cron schedule visually and get the expression.
Data Storage Converter
Convert bytes, KB, MB, GB, TB and their binary equivalents.
JSON Formatter
Format, validate and explore JSON with precise error reporting.
JSON Validator
Check whether JSON is valid and get the exact error position.