The Cron Alarm & Timer is a powerful tool that allows you to schedule alarms using cron expressions, intervals, specific times, or duration countdowns. The alarm will sound each time the schedule is triggered.

Timer Modes

Cron Mode

Cron expressions allow for flexible scheduling using five fields:

Minute (0-59)
Hour (0-23)
Day (1-31)
Month (1-12)
Weekday (0-6, Sunday = 0)

Use * for any value, */n for intervals, n-m for ranges, and n,m for lists.

Interval Mode

Set a simple interval (seconds, minutes, or hours) for recurring alarms.

Specific Times Mode

Add multiple specific times during the day when the alarm should trigger.

Duration Mode

Set a countdown timer with hours, minutes, and seconds. Useful for Pomodoro technique or focused work sessions.

Preset Cron Expressions

Quick-select from common cron patterns:

* * * * * - Every minute
*/5 * * * * - Every 5 minutes
*/15 * * * * - Every 15 minutes
0 9 * * 1-5 - Weekdays at 9 AM
0 0 * * * - Daily at midnight

Alarm Sounds

Choose from 6 built-in alarm sounds or upload your own custom audio file (MP3, WAV, OGG).

Adjust volume and duration to suit your preferences. Test any sound before saving.

Features

Trigger Counter - Track how many times each alarm has fired
Next Execution Preview - See when the alarm will next trigger
Auto-restart - Option to automatically restart after triggering
Multiple Alarms - Create and manage multiple alarms simultaneously
Persistent Storage - Alarms are saved in your browser

Browser Requirements

This tool uses the Web Audio API for sound generation. For custom sound uploads, your browser must support the audio formats you use.

Note: Keep the tab open for alarms to work. Browser background tab throttling may affect timing accuracy.