There are exactly 53 Sundays in the year 2012.
The answer to this question is not always simple. Most of the time, it will equal the number of weeks in a year, but that’s only true for some of the days of the week.
Most years have 365 days, but a leap year has 366 days. That adds up to 52 weeks (where each week is exactly 7 days) PLUS 1 or 2 additional days. The year 2012 has exactly 366 days.
Now if the year starts on a Sunday in a non-leap year, you end up with 53 Sundays. Or if either of the first two days lands on a Sunday during a leap year, then you can also get 53 Sundays. Check the calendars below for January and December of 2012 to see exactly where the year starts and ends.