Test and validate cron expressions with examples. See when your cron job will run next.
Runs daily at midnight
Predictions use standard 5-field cron; 6-field (seconds) syntax is not supported. Times are shown in your browser's local timezone.
A cron expression tells a scheduler when a job should run. Classic five-field syntax, the dialect used by
Linux crontab and most cloud schedulers, is a single line of
minute hour day-of-month month day-of-week
values. An asterisk matches every allowed value, commas build lists, hyphens create ranges, and a slash steps
through a range, so */5 * * * *
fires every five minutes and 0 9 * * 1-5
runs at 09:00 on weekdays.
As you type, this tester validates the field count, maps each field onto the five-slot breakdown strip, and composes a plain-English description of the resulting schedule. It targets the standard five-field format: dialects that add a leading seconds field, such as Quartz or AWS EventBridge schedules with six or seven fields, are rejected as invalid here.
Two gotchas save real debugging time. First, when both day-of-month and day-of-week are restricted, classic cron treats them as alternatives (either may match) rather than requiring both. Second, the schedule fires in the cron daemon's own timezone, which is not guaranteed to be UTC. Once your expression checks out, inspect auth headers in the JWT Debugger, test matching patterns in the Regex Tester, or tidy job definitions with the JSON Formatter & Validator.
Left to right, the fields are minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-7, where both 0 and 7 mean Sunday). For example, 0 9 * * 1-5 runs at 09:00 every Monday through Friday.
This tester implements standard five-field cron. Quartz, Spring, and AWS EventBridge dialects prepend a seconds field (and sometimes append a year field). Strip the extra leading field to validate the schedule here.
When only one of the two fields is restricted, the job runs on the matching days. When both are restricted, classic cron runs the job if either field matches, treating them as alternatives. That OR behavior surprises many people expecting both conditions to apply.
Use 0 9 * * 1-5, which means minute 0 of hour 9, every month, Monday through Friday. Adjust the hour for your local time, keeping in mind that the cron daemon interprets the schedule in its own timezone.
No. It validates the five fields and generates a human-readable description of the schedule. To confirm precise run dates, use your scheduler's own preview feature or check the cron environment for timezone and user context.