Date & Time

Cron Expression Generator & Parser

Craft and parse standard 5-field cron expressions with descriptions, field breakdowns, and next run times.

Format: minute hour day-of-month month day-of-week — for example 0 9 * * 1 or @daily.

Cron expressions are parsed entirely in your browser and are not uploaded to TechFixGen.

Your data stays private

This tool runs directly in your browser. The content you enter is processed locally and is not sent to TechFixGen servers. No account or signup is required.

Cron expressions, explained

What is a cron expression?

A cron expression is a shorthand for “when should this run?”. Systems like cron, CI pipelines, and cloud schedulers use it to describe repeating schedules in five fields. This tool parses the standard 5-field format into a plain-language description, a field breakdown, and the next five matching run times.

minute      hour      day-of-month   month      day-of-week
0–59        0–23      1–31           1–12       0–7 (0 and 7 = Sunday)

Values      lists: 1,15            ranges: 9-17
Steps       */15  (every 15)      ranges with steps: 0-30/10
Names       JAN, FEB ... DEC      SUN, MON ... SAT

Field syntax

  • Comma lists pick specific values: 1,15 means minutes 1 and 15.
  • Ranges cover a span: 9-17 hours is 09:00 through 17:00.
  • Steps repeat within a star or range: */15 every 15 minutes, 0-30/10 every 10 minutes in the first half hour.
  • Names work in the month and day-of-week fields: full or three-letter forms like JANUARY/JAN and MONDAY/MON, case-insensitive.
  • Day-of-week accepts 0 and 7 for Sunday.

Shorthand aliases

Common schedules have names. Entering an alias expands to the equivalent 5-field expression, which is shown in the result as the normalized form.

@yearly    0 0 1 1 *
@monthly   0 0 1 * *
@weekly    0 0 * * 0
@daily     0 0 * * *
@hourly    0 * * * *

@annually and @midnight are also accepted as aliases of @yearly and @daily.

How days of the month and week combine

The standard format treats the day-of-month and day-of-week fields as an AND combination when only one of them is restricted. When both are restricted, a run fires when either matches — this is the classic Vixie behaviour, and this tool calls it out explicitly so the result never surprises you.

What is not supported

6- and 7-field second-based formats, and the Quartz or AWS dialect characters ?, L, W, and # are rejected with a clear message instead of being guessed at. If you paste one, switch to the equivalent standard 5-field form or use a scheduler that supports that dialect.

Timezones

Expressions are evaluated in your browser's local timezone from the current moment, and the next five runs are shown as local times. Cron on your server evaluates in the server's timezone, so a schedule that matches here may need adjusting when the system time differs.

Privacy

Everything runs entirely in your browser. Cron expressions and the computed run times are not uploaded to TechFixGen servers and are not included in analytics events.

Frequently asked questions

What does a 5-field cron expression mean?

The five fields are minute, hour, day of month, month, and day of week. For example, 0 9 * * 1 runs at 09:00 on Mondays. This tool shows the meaning of every field in a plain-language breakdown.

How do I express 'every 15 minutes' or 'every weekday at 9am'?

Every 15 minutes is */15 * * * *. Weekdays at 9am is 0 9 * * 1-5. Both are available as presets, along with hourly, daily, midnight, weekly, and monthly schedules.

Does this support the 6- or 7-field formats with seconds?

No. 6- and 7-field second-based formats, and the Quartz/AWS characters ?, L, W, and #, are rejected with a clear message. This tool uses the standard 5-field cron format used by cron itself.

How are the next run times calculated?

Runs are found by scanning forward minute by minute from the current moment in your browser's local timezone. The next five matching times are shown as local dates and times.

Why does a schedule with both day fields fire twice a month?

When both day-of-month and day-of-week are restricted, the standard (Vixie) rule is an OR: a run fires when either matches. The tool flags this explicitly whenever it applies.

Is my cron expression uploaded anywhere?

No. Parsing and run-time calculation happen entirely in your browser. Expressions and result times are not uploaded to TechFixGen servers and are not included in analytics events.