# Cron Expression Tester

URL: https://phishdestroy.io/developer-tools/cron-expression-parser
Category: General dev
Where it runs: Runs locally (nothing you enter is uploaded)

Enter a five-field cron expression and see the next five times it would run, in your local time and in UTC. Useful for checking the schedule of a job that refreshes a blocklist or pulls a threat feed.

## Example input

Weekday working hours

```
*/15 9-17 * * 1-5
```

Lists the next five quarter-hour slots between 09:00 and 17:45 on Monday to Friday, in your local time with the UTC time beside each.

## FAQ

### What syntax does it understand?

The five standard fields (minute, hour, day of month, month, day of week) with *, single numbers, ranges (9-17), comma lists of numbers (1,15) and */n steps. It lists the next five matching times; it does not describe the expression in words.

### Why does my expression show fewer runs or none?

Month and weekday names (JAN, MON), steps on ranges (1-30/5), mixed lists (1-5,10), Sunday as 7 and six-field expressions with seconds are not supported. Day of month and day of week must both match, while standard cron runs when either does; */n on day of month or month counts from 0 (*/10 gives the 10th, 20th and 30th), and only the next 100,000 minutes (about 69 days) are searched.

### Is anything sent to a server?

No. The run times are computed in your browser from its clock and time zone.

## Related tools

- [Cron Schedule Builder](https://phishdestroy.io/developer-tools/cron-schedule-builder)
- [Unix Timestamp Converter](https://phishdestroy.io/developer-tools/unix-timestamp-converter)
- [Date Calculator](https://phishdestroy.io/developer-tools/date-calculator)
- [Duration Converter](https://phishdestroy.io/developer-tools/duration-converter)

All tools: https://phishdestroy.io/developer-tools