Date & Time Tools.

Time is the most universal shared resource in professional work, and also one of the most error-prone to handle precisely. Timezones shift with daylight saving transitions, calendar years vary in length, and coordinating across continents requires exact conversion rather than mental arithmetic. The date and time tools on Powertoys.Online handle these tasks with precision.

The interactive Calendar renders a clean full-year view with public holiday data for major countries. Navigate between months, identify what day any future date falls on, and check which public holidays fall within a planning period. No account sync is required, no notifications, no calendar apps involved — just dates. Useful for project planning, scheduling across regions, and identifying working days in any given month.

The Timezone Converter is built for remote teams and international coordination. Enter any date and time, select a source timezone, and see the equivalent time in dozens of world cities simultaneously — including regions that use non-hour UTC offsets such as India (UTC+5:30), Iran (UTC+3:30), and Nepal (UTC+5:45). The converter handles daylight saving time transitions automatically based on the date you enter, so you always see the correct local time rather than a fixed offset that may be wrong during DST.

The Leap Year Viewer instantly determines whether any year is a leap year using the Gregorian calendar rule: divisible by 4, except century years which must be divisible by 400. This rule catches people out in software development — date arithmetic, billing cycle calculations, and file naming conventions can all produce subtle errors when a leap year is handled incorrectly. The viewer also shows the next upcoming leap years from any reference point.

All date and time tools run entirely in your browser. The timezone converter uses a bundled timezone database — no API calls, no external dependencies once the page loads.

Frequently Asked Questions

Which countries' public holidays does the calendar include?

The calendar includes public holiday data for major countries including the United States, United Kingdom, Australia, Canada, Germany, France, India, and others. Holiday data is compiled from official government sources and updated periodically. Select your country from the calendar's country selector to filter to relevant holidays.

Does the timezone converter account for daylight saving time?

Yes. The timezone converter uses a full IANA timezone database that includes daylight saving rules for every timezone. When you enter a date that falls within a DST period, the converter automatically applies the correct offset — so the displayed times are accurate for that specific date, not just a fixed UTC offset.

How do you calculate whether a year is a leap year?

Under the Gregorian calendar: a year is a leap year if it is divisible by 4, except for century years (divisible by 100), which must also be divisible by 400. For example: 2000 was a leap year (divisible by 400), 1900 was not (divisible by 100 but not 400), and 2024 is a leap year (divisible by 4, not a century year).

Can I use the timezone converter to find meeting times for remote teams?

Yes. Enter the meeting time and date in your local timezone, then view the equivalent time in all other participants' cities simultaneously. The converter displays results for dozens of world cities so you can identify a time that falls within working hours for all locations.

Does the calendar tool work offline?

Once the page has loaded, the calendar works without an internet connection. The holiday data and calendar logic are bundled with the page. No network requests are made when navigating between months or changing the country.

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