Lintcron
See exactly which cron field is wrong — and why.
Type a cron expression, get instant field-by-field feedback. See what it means in plain English and when it runs next. Everything happens in your browser.
dow: value 8 is out of range (0-7)
What Lintcron Does
Lintcron is a browser-based cron expression validator. It parses your expression field by field, highlights errors with specific messages, translates valid expressions into plain English, and shows the next scheduled run times.
Most cron tools tell you “invalid expression.” Lintcron tells you which field is wrong and why — like a linter for cron.
How It Works
5/6/7-field cron
Standard, seconds, and Quartz formats. Auto-detected.
Live feedback
Validates as you type. Each field gets its own status.
Plain English
Translates valid expressions into readable descriptions.
Next run times
Shows upcoming execution dates so you can verify the schedule.
Fully private
No server calls. Your expressions stay in your browser.
Light & dark
Follows your system preference or switch manually.
Cron Syntax Quick Reference
| Field | Allowed Values | Special Characters |
|---|---|---|
| Minute | 0-59 | * , - / |
| Hour | 0-23 | * , - / |
| Day of Month | 1-31 | * , - / |
| Month | 1-12 or JAN-DEC | * , - / |
| Day of Week | 0-7 (0 and 7 = Sunday) | * , - / |
Who It's For
Backend developers setting up scheduled jobs. DevOps engineers writing crontab entries for deployment scripts. SREs configuring monitoring alerts. Anyone who has stared at five fields separated by spaces and wondered if they got the day-of-week right.
Why “Lintcron”?
“lint” as in linting — checking code for errors. “cron” as in the Unix job scheduler. Lintcron is a linter for cron expressions.
Your data stays put
No accounts. No server calls. Everything runs in your browser. See our Privacy Policy for details.