free_tool
Cron Expression Explainer
Five fields and a lot of asterisks. Paste a cron expression and get it back in plain English, plus the next five times it will actually fire, so you can be sure "0 0 1 * *" means what you think before it ships. It runs in your browser.
In plain English
At 09:00, on Monday, Tuesday, Wednesday, Thursday, and Friday.
Next 5 runs
Calculating…
Computed in UTC, the default for most schedulers and CI. Your local equivalents are shown alongside.
Cron is fine until a job overruns, double-fires, or silently dies and nobody notices for a week. I set up scheduled work that's idempotent, observable and alertable.
Make your jobs reliable: book a callStandard 5-field cron, with ranges (1-5), lists (1,3,5), steps (*/15), names (MON, JAN) and macros (@daily). Day-of-month and day-of-week follow the usual rule: when both are set, a run matches if either does.
read_before_you_ship
The schedule you meant, not the one you typed
Cron's syntax is terse enough that a job firing every minute instead of once a day is a single misplaced asterisk away. Seeing the next few real run times is the fastest way to catch that before it's a 2am pager or a bill for a million executions.
The classic trap is day-of-month combined with day-of-week. Most people read it as "and"; cron reads it as "or" when both are set, so 0 0 13 * 5 runs every Friday and the 13th, not only on Friday the 13th. The run list makes that obvious at a glance.
Scheduled jobs you can't fully trust?
Overlapping runs, silent failures, jobs that fire twice or not at all. I'll make your scheduled work idempotent, observable and alertable. Book a call, or leave your email.