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**18 October 2018**** minus 100 days** will be

10th July 2018

For example

- What is 100 years before Today? (Today minus 100 years)
- What is 8 years from 21 March 2024? (21 March 2024 plus 8 years)
- What is 15 years before Yesterday? (Yesterday minus 15 years)
- What is 500 months from 4 April 2025? (4 April 2025 plus 500 months)
- What is 2 days before Tomorrow? (Tomorrow minus 2 days)
- What is 4 weeks before 14 April 2020? (14 April 2020 minus 4 weeks)

The **Gregorian calendar** is the most widely used internationally civil calendar. It is named after Pope Gregory 13th, who introduced it in **October 1582**.

The Gregorian calendar is a **solar calendar**. A regular Gregorian year consists of 365 days, but as in the Julian calendar, in certain years, a leap year, a **leap day is added to February**

The months of **April, June, September, and November** have **30 days**, while the **rest have 31 days** except for **February**, which has **28 days** in a standard year, and **29 in a leap year**.

For best results, please use dates after 1752 and **verify any data** if you are doing genealogy research.