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Cron Expression Builder

Build a cron expression by clicking instead of memorizing syntax. Pick minutes, hours, days, months and weekdays with simple controls or start from a preset, watch the expression and its plain English meaning update live, and check the next run times before you copy it.

Everything runs locally in your browser. Your data never leaves your device.

MinutesHoursDay of monthMonthDay of week

Use the controls below, start from a preset, or paste an expression here to load it into the controls.

Build it field by field

Minutes*

Matches every minute, written as *.

Hours*

Matches every hour, written as *.

Day of month*

Matches every day of the month, written as *.

Month*

Matches every month, written as *.

Day of week*

Matches every day of the week, written as *.

In plain words

Every minute.

Next run
in 2 seconds
Sat, 11 Jul 2026, 21:00

Upcoming runs

  1. 1.Sat, 11 Jul 2026, 21:00in 2 seconds
  2. 2.Sat, 11 Jul 2026, 21:01in 1 minute 2 seconds
  3. 3.Sat, 11 Jul 2026, 21:02in 2 minutes 2 seconds
  4. 4.Sat, 11 Jul 2026, 21:03in 3 minutes 2 seconds
  5. 5.Sat, 11 Jul 2026, 21:04in 4 minutes 2 seconds
  6. 6.Sat, 11 Jul 2026, 21:05in 5 minutes 2 seconds
  7. 7.Sat, 11 Jul 2026, 21:06in 6 minutes 2 seconds
  8. 8.Sat, 11 Jul 2026, 21:07in 7 minutes 2 seconds
  9. 9.Sat, 11 Jul 2026, 21:08in 8 minutes 2 seconds
  10. 10.Sat, 11 Jul 2026, 21:09in 9 minutes 2 seconds

Times shown in your local timezone (UTC). The machine running the job decides the real timezone, and servers often use UTC.

Next steps

Keep going. These tools open with your result loaded in.

Cron Expression Explainer

Paste a cron expression and get a plain English explanation, a field by field breakdown and the next times it would run, in your local timezone or UTC. Reads five field crontab syntax, six fields with seconds, names like MON and macros like @daily.

dev

Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

textconverter

Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

text

Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

textdev

Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

textdev

Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

textdev

UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

devuuid

Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

devconvertertext

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base up to 36. Type into any field and the others update as you go. Handles huge integers without losing precision and accepts 0x, 0b and 0o prefixes.

devconvertercalculator

About the Cron Expression Builder Tool

This tool builds a cron expression for you, so you pick what you want instead of remembering the syntax. Each field of the schedule (minute, hour, day of month, month and day of week, plus an optional seconds field) has simple modes: run on every value, every nth value, a set of specific values you click together, or a range. The expression updates live as you click, color coded by field, next to a plain English sentence saying what it means and a list of the exact times it would run next.

It works in both directions. Paste an existing expression, or send one over from the Cron Expression Explainer, and the controls fill themselves in from it. A field that uses syntax the simple modes cannot show, like a mixed list with steps, switches to a custom mode where you edit its raw text directly.

What you can do

  • Build a cron expression by clicking values instead of writing syntax.
  • Start from a preset like every 5 minutes, daily at midnight or weekdays at 09:00.
  • Pick specific minutes, hours, days, months or weekdays from a grid.
  • Set every nth schedules like */15 with a single number.
  • Read the schedule as a plain English sentence while you build it.
  • Check the next run times in your local timezone or in UTC before you copy it.
  • Load an existing expression into the controls to adjust it.
  • Add a seconds field for schedulers that use six field syntax.

How to use the Cron Expression Builder

  1. 1Start from a preset, paste an existing expression, or begin with every minute.
  2. 2Set each field's mode and pick its values, step or range.
  3. 3Read the plain English summary and the upcoming runs to confirm the schedule.
  4. 4Copy the expression into your crontab or scheduler.

The field modes

Every field offers the same choices. Every writes a * and matches all values. Every nth writes a step like */5, counted from the field's lowest value, and shows you which values that actually hits. Specific lets you click values together into a list like 0,15,30, and Range writes a span like 9-17. The Custom mode takes raw cron text for anything else, like 1-5,10 or 10-30/5, and validates it as you type.

Switching modes carries your picks over where that makes sense. A step or range expands into its selected values, and picked values collapse into the range that spans them.

Loading an existing expression

Pasting an expression fills the controls in from it, including month and weekday names like JAN and MON-FRI and the macros @hourly through @yearly, which expand into their five field form. When a field is written in a way the simple modes cannot represent, that field falls back to the custom mode with its raw text kept editable, and the rest of the controls still work normally.

Check before you copy

Cron has traps. When both day fields are restricted, classic cron runs when either one matches, and the tool warns you when a schedule falls into that case. The upcoming runs list shows the concrete times the expression fires, in your local timezone or in UTC, so you can confirm the schedule does what you meant. For a full field by field breakdown of the result, send it to the Cron Expression Explainer.

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