How Many Days Are in Half a Year? 182 or 183
Half a year is 182.5 days on average — in practice 181, 182, 183 or 184 depending on which half you count. See why the halves are not equal.
Half of 365 is 182.5, which is not a number of days you can point at on a calendar. The practical answer is 182 or 183, and if you mean a specific half of a specific year it can be 181 or 184.
The Arithmetic Answer
- Common year: 365 ÷ 2 = 182.5 days
- Leap year: 366 ÷ 2 = 183 days
Only a leap year splits evenly.
The Calendar Answer Is Lopsided
Counting from January 1 to July 1 does not give you half the year, because the first six months are shorter than the last six.
| Period | 2026 (common) | 2028 (leap) |
|---|---|---|
| Jan 1 → Jul 1 | 181 days | 182 days |
| Jul 1 → Dec 31 | 183 days | 183 days |
| Jan-Jun inclusive | 181 days | 182 days |
| Jul-Dec inclusive | 184 days | 184 days |
January through June holds 181 days in a common year; July through December holds 184. The second half is three days longer, entirely because July and August are both 31 days while February is 28.
Half a Year in Weeks
Twenty-six weeks is exactly 182 days, which is why 26 weeks is the cleaner way to express half a year for anything scheduled weekly — biweekly payroll, rotas, subscription cycles. See [how many weeks are in half a year](/blog/weeks-in-half-a-year).
Which Number to Use
- Contracts and notice periods — count actual calendar dates, not 182. "Six months" in a contract almost always means to the same date six months later, which the [add or subtract days tool](/tools/date-add-subtract) handles with proper month-end clamping.
- Interest and pro-rata calculations — financial conventions often fix the half-year at 182.5 or 180 days regardless of the calendar. Check which convention applies.
- Project planning — 26 weeks is more useful than 182 days, because work is scheduled in weeks.
Counting a Specific Span
For an exact figure between two dates, the [date difference calculator](/tools/date-difference) counts calendar days and handles leap years and daylight-saving transitions correctly.