It is common to hear the answer to the above question as 52 weeks. Although that’s true, it is not technically right. People forget to add a day or two as we will see the explanation below.

This is the reason. An exact count of 52 weeks is not technically a full year. A full year is 52 weeks plus a day if it’s a common year or plus 2 days if it is a leap year.
A common year has 365 days while a leap year has 366 days. Remember in the leap year, February has 29 days while in common year it’s February has 28 days. So if a leap year has 366 days and a week is 7 days then a leap year has 52 weeks and 2 days. Note that it is not just 52 weeks but it is 52 weeks and 2 days.

A common year has 365 days. 365 days divided by 7 days you get 52 weeks and 1 day. Again it is not just 52 weeks its 52 weeks and a day.
So to answer the question; A leap year has 52 weeks 2 days and a common year has 52 weeks and one day.