Cron Expression Parser & Builder

Parse an existing cron expression or build one field by field. Validate schedules, see human-readable descriptions, and preview the next run times in UTC.

  • Runs entirely in your browser
  • No data stored or sent to a server
  • Free forever — no signup
  • Instant conversion

Input and Output

Use the interactive encoder and decoder on this page to process your text.

Learn more about cron expressions

How to Parse and Build Cron Expressions

Cron Expressions

Parse vs Build

Parse mode validates an existing cron expression and lists the next run times. Build mode lets you set each field individually and generates the expression for you.

Cron Format

Supports standard 5-field cron (minute hour day month weekday) and 6-field cron with seconds. Example: 0 9 * * 1-5 runs at 9:00 AM UTC on weekdays.

Visualizer

After parsing or building, a lightweight timeline shows upcoming run times in UTC so you can sanity-check the schedule at a glance.

Frequently asked questions

What timezone are next run times in?

All next run times are shown in UTC.

Can I build a cron expression field by field?

Yes. Switch to Build mode, fill in each field, and click Run to validate and preview the schedule.