How many days are in a year? In the calendar almost everyone uses — the Gregorian — a normal year has 365 days, and a leap year has 366. But that isn't the only answer: the world's other calendars count the year differently. Here's the full picture.
Check any year's exact length on our year overview pages, or read about the Gregorian calendar.
The short answer (Gregorian calendar)
| Year type | Days |
|---|---|
| Common year | 365 |
| Leap year | 366 (adds 29 February) |
A year is roughly how long Earth takes to orbit the Sun — about 365.2422 days. Since you can't have a fraction of a day on the calendar, we use 365 most years and add a 29th of February every four years (with century exceptions) to stay aligned. 2026 has 365 days; the next leap year is 2028.
Why 365.2422 and not exactly 365?
That extra ~0.2422 of a day is exactly why leap years exist. Four years of that fraction add up to almost a full day — so we insert one. The small remaining error is corrected by skipping leap years in 3 out of every 4 century years (1700, 1800, 1900 were not leap years; 2000 was).
How many days in other calendars?
This is where it gets interesting — not every calendar has 365 days:
| Calendar | Days in a year | Type |
|---|---|---|
| Gregorian | 365 / 366 | Solar |
| [Islamic (Hijri)](/islamic-calendar) | ~354–355 | Lunar |
| [Hebrew](/hebrew-calendar) | 353–385 | Lunisolar |
| [Chinese](/chinese-calendar) | 354 / 384 | Lunisolar |
| [Hindu](/hindu-calendar) | ~354–385 | Lunisolar |
| Ethiopian | 365 / 366 (13 months) | Solar |
- Lunar calendars (Islamic) follow the Moon — 12 lunar months ≈ 354 days, about 11 days shorter than the solar year, which is why Islamic dates drift earlier each year.
- Lunisolar calendars (Hebrew, Chinese, Hindu) add a whole "leap month" in some years to catch up with the Sun — so their year can jump from ~354 to ~384 days.
That's why your birthday on the Gregorian calendar lands on a different date in these other systems each year.
How many days, weeks, hours in a Gregorian year?
| Unit | In a 365-day year |
|---|---|
| Days | 365 |
| Weeks | 52 weeks + 1 day (52.14) |
| Hours | 8,760 |
| Minutes | 525,600 |
| Seconds | 31,536,000 |
(A leap year has 8,784 hours.)
Quick answers
How many days are in a year? 365 in a common year, 366 in a leap year. 2026 has 365 days.
How many weeks are in a year? 52 weeks and 1 extra day (or 2 in a leap year) — so most years touch 53 ISO week numbers.
Do all calendars have 365 days? No. The Islamic year has about 354 days; the Hebrew, Chinese and Hindu calendars range from about 353 to 385 days because they add leap months.
How many hours are in a year? 8,760 hours in a 365-day year, and 8,784 in a leap year.