Date Calculator: Duration Difference, Add and Subtract

Start Date (dd/mm/yyyy):
End Date (dd/mm/yyyy):


This versatile tool enables you to calculate the duration in days, months, and years between two dates. It also allows you to add or subtract days, weeks, months, and years from a given date.

How to calculate duration between two dates?

To calculate the duration between two dates, simply input the start date and end date, and then click the "Subtract" button. This will provide you with the number of days, months, and years that span between the two dates.

How to calculate a target date?

To calculate a target date, input the start date and specify the number of years, months, weeks, and days. Afterward, click the "Add" button to determine the end date corresponding to your desired time frame.

What is the purpose of the Gregorian calendar?

The Gregorian calendar is a solar calendar used as the standard calendar in many parts of the world. Its primary purpose is to provide a consistent and widely accepted system for measuring and organizing time. The Gregorian calendar is designed to align with the Earth's annual orbit around the Sun and provides a framework for determining the duration of days, months, and years. It serves as a practical tool for scheduling events, coordinating activities, and facilitating a shared understanding of dates and time across different cultures and regions.

Which countries do not use the Gregorian calendar?

Most countries in the world use the Gregorian calendar as their official calendar. However, there are a few exceptions where other calendar systems are followed to some extent:

  1. Islamic Calendar (Hijri Calendar): The Islamic calendar is widely used in Muslim-majority countries, and it is a lunar calendar based on the cycles of the Moon. It is used for determining religious observances and holidays.

  2. Hebrew Calendar: The Hebrew calendar is used in Jewish communities worldwide, and it is a lunisolar calendar. It is based on both lunar and solar cycles and is used for determining religious holidays and observances.

  3. Buddhist Calendar: Various Buddhist countries follow their own traditional lunar or lunisolar calendars based on local customs and traditions. Examples include the Thai Buddhist calendar and the Tibetan calendar.

  4. Chinese Calendar: The Chinese calendar, also known as the Lunar Calendar or the Agricultural Calendar, is widely used in China and other East Asian countries. It is a lunisolar calendar that combines lunar and solar cycles and is used for determining traditional holidays and festivals.

It's important to note that even in countries where alternative calendars are used for religious or cultural purposes, the Gregorian calendar is often used for civil and administrative purposes, such as official documents, international communication, and business activities.