Precision time tools for every timezone

Date & Time Calculator — Free Online

Professional-grade date and time calculators trusted by millions. Accurate across all timezones, leap years, and date formats.

Available in Your Country

Pre-configured with your local timezone, date format, and public holidays.

الإمارات

বাংলাদেশ

ශ්‍රී ලංකාව

ประเทศไทย

All Free Date & Time Tools

Every tool is free, instant, and works directly in your browser — no sign-up required.

Date Difference Calculator

Calculate the exact number of days, weeks, or months between any two dates.

Add or Subtract Days Calculator

Add or subtract any number of days, weeks, or months from a date.

Calculate your exact age in years, months, and days from your birthdate.

Time Zone Converter

Convert time between any two timezones worldwide with DST accuracy.

Days Until Calculator

Count the exact number of days until any future date or event.

Weekday Calculator

Find out what day of the week any date falls on — past or future.

Business Days Calculator

Count working days between two dates, excluding weekends and holidays.

Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and vice versa.

Date Format Converter

Convert dates between different formats: DD/MM/YYYY, MM/DD/YYYY, ISO 8601, and more.

Leap Year Checker

Check whether any year is a leap year using the Gregorian calendar formula.

Time Duration Calculator

Calculate the exact duration between two times in hours, minutes, and seconds.

Calendar Week Number

Find the ISO week number for any date and the start/end of that week.

Why DateTimeLab?

🎯

Accurate

Leap year aware, DST-correct, and validated against ISO 8601 standards.

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Fast

Instant results with no server round-trips. All calculations run in your browser.

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Free Forever

No subscriptions, no sign-ups, no paywalls. Every tool is 100% free.

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Expert-Verified

Formulas validated by Vipul Jaganiya, Computer Science expert in Calendar Mathematics.

About the Expert

👨‍💻

Vipul Jaganiya

Computer Science · Calendar Mathematics & Timezone Engineering

DateTimeLab was built by Vipul Jaganiya, a Computer Science graduate specializing in Calendar Mathematics and Timezone Engineering. Every formula on this site is validated for accuracy across leap years, Daylight Saving Time transitions, and historical calendar reforms. Tools are tested across all 13 countries and their respective public holiday datasets.