Date & Time Tools

Calculate date differences, convert Unix timestamps, find day of year, create countdown timers, use a precise stopwatch, and convert between world timezones.

Date Difference Calculator

Calculate the difference between two dates in days, weeks, months, and years with workday options.

Unix Timestamp Converter

Convert between Unix timestamps and human-readable dates in any timezone.

Day of Year Calculator

Calculate day number, week number, quarter, and leap year status for any date.

Countdown Timer

Create live countdown timers to any date/time with localStorage persistence.

Stopwatch

Start, stop, lap, and reset with millisecond precision. Track multiple laps.

Time Zone Converter

Convert time between world timezones using the browser's Intl API.

Frequently Asked Questions

How does the date difference calculator work?

Enter two dates and the calculator shows the exact difference in years, months, weeks, and days. It also offers workday counting options that exclude weekends.

Does the countdown timer keep running when I close the page?

The countdown target time is saved in localStorage, so when you return, it picks up from the correct remaining time rather than resetting.

Which timezones are supported?

The timezone converter uses your browser's built-in Intl API, supporting all IANA timezones worldwide — over 400 timezone options.