The variety of weeks in a 12 months can range relying on the calendar system used. The Gregorian calendar, which is essentially the most extensively used calendar on the planet, has 52 weeks in a normal 12 months and 53 weeks in a bissextile year. A bissextile year is a 12 months that’s divisible by 4 however not by 100, or a 12 months that’s divisible by 400. The 12 months 2025 isn’t a bissextile year, so it is going to have 52 weeks.
The Gregorian calendar was launched in 1582 by Pope Gregory XIII to appropriate errors that had accrued within the Julian calendar, which was the calendar that was used beforehand. The Julian calendar had a bissextile year each 4 years, which induced it to float out of sync with the photo voltaic 12 months. The Gregorian calendar corrects this by having a bissextile year each 4 years, apart from years which might be divisible by 100 however not by 400.