How Many Weeks Are in Half a Year?

Half a year is approximately 26 weeks, but there is no single exact answer unless “half” is defined. A mathematical half of a common year is 182.5 days, while six calendar months can contain different numbers of days.

Half of the Year's Duration

A common year has 365 days:

365 ÷ 2 = 182.5 days = 26 weeks and 0.5 day

A leap year has 366 days:

366 ÷ 2 = 183 days = 26 weeks and 1 day

This calculation describes duration, not a practical date boundary at noon in the middle of a day.

January Through June

The first six calendar months contain 181 days in a common year and 182 in a leap year. That equals 25 weeks and 6 days, or exactly 26 weeks in a leap year.

July Through December

The last six months always contain 184 days, which equals 26 weeks and 2 days. The two calendar halves differ because months have unequal lengths.

Six Months From a Date

Adding six calendar months is not the same as adding 26 weeks. Twenty-six weeks is 182 days. Six months from August 31 may require an end-of-month rule because February has no 31st day.

For subscriptions, contracts, and age calculations, use the calendar-month rule stated in the agreement. For a fixed-duration experiment, use an exact number of days or seconds.

Planning Shortcut

Use 26 weeks for rough scheduling. For deadlines, payroll, interest, or legal periods, calculate from the actual start date and specify whether the end date is included.

Bottom Line

“Half a year” is about 26 weeks. Depending on whether it means half the total duration, January through June, July through December, or six months from a date, the exact span ranges from 181 to 184 days.