How Many Days in a Leap Year? (Simple Answer + 2025 Guide) Updated 2025
Answer: A leap year has 366 days. The extra day is February 29. Leap years keep our calendar in step with Earth’s orbit around the Sun.
Below you’ll find the leap-year rule, a checker to test any year, common mistakes, and a table of recent and upcoming leap years.
The Leap-Year Rule (Easy Version)
Use this three-step rule to know if a year has 365 or 366 days:
- Divisible by 4? → It’s a leap year …
- Except if it’s also divisible by 100 → then it’s not a leap year …
- Except again if it’s divisible by 400 → then it is a leap year.
Examples: 2024 and 2028 are leap years. 2100 is not. 2000 was a leap year.
Takeaway: The rule keeps our calendar close to the real solar year while staying simple to use.
Takeaway: You can test any year in seconds and know if it has 365 or 366 days.
Why Do We Have Leap Years?
Earth’s trip around the Sun takes about 365.2422 days, not a perfect 365. If we never added a day, our calendar would slowly drift. Seasons would slide away from their usual dates.
Why February?
February is the shortest month, so it’s the easiest place to add the extra day. In leap years, February has 29 days instead of 28.
Takeaway: Leap years keep dates and seasons aligned over the long run.
Recent and Upcoming Leap Years (2000–2040)
Here are leap years you’ll likely bump into in daily life. (2025 is not a leap year.)
| Leap Year | Days | Notes |
|---|---|---|
| 2000 | 366 | Century year divisible by 400 → leap year |
| 2004 | 366 | Every 4 years pattern |
| 2008 | 366 | Every 4 years pattern |
| 2012 | 366 | Every 4 years pattern |
| 2016 | 366 | Every 4 years pattern |
| 2020 | 366 | Every 4 years pattern |
| 2024 | 366 | Most recent leap year |
| 2028 | 366 | Next leap year after 2025 |
| 2032 | 366 | Every 4 years pattern |
| 2036 | 366 | Every 4 years pattern |
| 2040 | 366 | Every 4 years pattern |
Takeaway: Most leap years follow the 4-year rhythm, with small adjustments for century years.
Common Mistakes About Leap Years
“Every 4 years, no exceptions.”
Close, but not quite. Century years break the pattern unless they also divide by 400. That’s why 2000 was a leap year, but 2100 will not be.
“Leap years happen twice a decade.”
They usually show up every four years, so sometimes you’ll see two within the same decade and sometimes only one. It depends on where the decade starts.
“February always has 28 days.”
In leap years, February has 29 days. That one extra day keeps the calendar and the seasons in sync.
Takeaway: Remember the 4 / 100 / 400 rule and you won’t get tripped up.
Keep Learning
- See the basics on our How many days in a year (home) page.
- Convert leap years into weeks, hours, minutes, and seconds.
- Estimate working days in a year for planning and payroll.
- Meet the team on our About page or contact us with questions.
Frequently Asked Questions
How many days are in a leap year?
A leap year has 366 days. The extra day is February 29, added to keep the calendar aligned with the seasons.
Is 2025 a leap year?
No. 2025 is a common year with 365 days. The next leap year after 2024 is 2028.
What is the rule for leap years?
Divisible by 4? Leap year. Divisible by 100? Not a leap year—unless it is also divisible by 400, in which case it is a leap year. This rule keeps the calendar close to the solar year.
Why does February get the extra day?
February is the shortest month, so placing the extra day there is the simplest fix. It bumps February from 28 to 29 days in leap years.
How often do leap years happen?
Roughly every four years. Century years adjust the pattern so our long-term average stays close to the real solar year length of about 365.2422 days.