Cron Expression in JS
Validate standard 5-field Unix cron expressions: minute, hour, day-of-month, month, day-of-week.
Try it in the JS tester →Pattern
regexJS
^(\*|([0-5]?\d))\s+(\*|([01]?\d|2[0-3]))\s+(\*|([1-9]|[12]\d|3[01]))\s+(\*|([1-9]|1[0-2]))\s+(\*|[0-7])$JavaScript / ECMAScript code
jsJavaScript
const re = new RegExp("^(\\*|([0-5]?\\d))\\s+(\\*|([01]?\\d|2[0-3]))\\s+(\\*|([1-9]|[12]\\d|3[01]))\\s+(\\*|([1-9]|1[0-2]))\\s+(\\*|[0-7])$", "");
const input = "0 9 * * 1";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).
How the pattern works
Each of the five fields is validated against its allowed range. Minute: 0–59. Hour: 0–23. Day-of-month: 1–31. Month: 1–12. Day-of-week: 0–7 (0 and 7 both mean Sunday). Each field also accepts * for any value.
Examples
Input
0 9 * * 1Matches
0 9 * * 1
Input
*/15 * * * *No match
—Input
60 25 * * *No match
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