Describe a cron expression in plain English and see its next run times.
About this tool
Enter a standard 5-field cron expression to see a plain-English description and its next 5 scheduled run times (UTC). Pick a common preset below to get started quickly. This v1 is cron-string-in, human-readable-out — a visual builder and the reverse (English-to-cron) direction are not yet supported.
Enter a cron expression (or pick a preset) and Tabreon instantly shows a plain-English description and its next 5 scheduled run times, entirely in your browser.
Why use Tabreon for this?
Parsing runs client-side — the schedule you enter, which may reveal internal job names or infrastructure details, never leaves your browser.
Common schedules are one click away via presets, no cron syntax memorization required.
Shows both a human-readable description and concrete upcoming run times, not just one or the other.
How to read a cron expression
1Enter or pick a schedule. Type a 5-field cron expression, or click a preset like "Every day at 9am" to fill it in.
2Read the description. A plain-English sentence describes exactly when the schedule fires.
3Check the next run times. The next 5 scheduled run times (in UTC) are listed below the description.
What is a cron expression?
A cron expression is a compact 5-field syntax (minute, hour, day-of-month, month, day-of-week) used by Unix cron, CI pipelines, and job schedulers to describe a recurring schedule — for example, `0 9 * * 1` means "9:00 AM every Monday." The syntax is powerful but not immediately readable, which is why translating it into plain English and concrete dates is a common debugging need.
How Tabreon handles your data
Parsing and calculation run entirely in your browser using the cronstrue and cron-parser libraries — the expression you enter is never transmitted to a server.
Key features
Plain-English description of any standard 5-field cron expression
Next 5 scheduled run times, computed in UTC
One-click presets for common schedules
Clear error message for an invalid cron expression
Common use cases
Confirming a CI pipeline's cron trigger actually runs when you expect before merging a config change
Understanding an unfamiliar cron schedule found in a legacy crontab file
Double-checking a scheduled job's next few run times before an on-call handoff
Common mistakes & limitations
v1 is cron-string-in, human-readable-out only — there is no reverse direction (typing "every day at 9am" to generate the cron string) and no visual dropdown-based builder yet.
Only standard 5-field cron syntax is supported; some schedulers' 6-field (with seconds) or non-standard extensions may not parse correctly.
Frequently asked questions
No. Parsing and calculation happen locally in your browser using the cronstrue and cron-parser libraries — your input is never transmitted to a server.
Next-run times are computed and displayed in UTC, since that's how most schedulers (cron, CI systems) interpret cron expressions by default unless configured otherwise.
Not yet — v1 only converts a cron expression into a description and run times, not the reverse. This is on the backlog as a fast-follow.