Glossary / Developer basics
Glossary · Developer basics · checked Oct 24, 2026
Cron expression
Short answerA cron expression is five fields, minute hour day-of-month month day-of-week, that say when a scheduled job runs. */15 9-17 * * 1-5 is every 15 minutes, 9 AM to 5 PM, Monday to Friday.
Why it matters
Off-by-one fields and time zones are the classic bugs: most servers and CI schedulers run cron in UTC.
Our number
Our cron expression tool explains an expression in words and lists its next run times.
Go deeper on this site
Where it shows up here
It appears on 4 pages of this site: 3 Free tools, 1 Article. A few to start with:
Sources
- POSIX crontab specification: pubs.opengroup.org/onlinepubs/9699919799/utilities/crontab.html (checked Oct 24, 2026)
Related terms
Up next
Go deeperCron expression explainerThe page on this site that does the most with this term.Read it next →Also worth your time
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