##
**13 January 2020**** minus 7 days** will be

6th January 2020

For example

- What is 300 weeks from Today? (Today plus 300 weeks)
- What is 700 weeks from 20 August 2020? (20 August 2020 plus 700 weeks)
- What is 21 weeks before Yesterday? (Yesterday minus 21 weeks)
- What is 90 years before 29 July 2020? (29 July 2020 minus 90 years)
- What is 60 years from Tomorrow? (Tomorrow plus 60 years)
- What is 7 months before 15 January 2020? (15 January 2020 minus 7 months)

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.