In 1 days there are 0.0000273791 centuries. Meanwhile in 1 centuries there are 36,524.25 days. Keep reading to learn more about each unit of measure and how they are calculated. Or just use the Centuries to Days calculator above to convert any number.
* Values rounded to 6 decimal places for readability
To convert days to centuries, divide the number of days by the number of days in one century.
Basic rule (365-day years):
centuries = days ÷ 36,500
(because 1 century = 100 years and 1 year = 365 days, so 100 × 365 = 36,500 days)
More accurate rule (with leap days):
Centuries can include extra days from leap years. In many 100-year spans, you’ll have about 24 to 25 leap days, depending on where the century falls in the calendar.
Quick example:
A common estimate is 36,500 days (100 years x 365 days).
If you include leap years, a century is closer to 36,524 or 36,525 days, depending on the exact 100-year span.
Use this simple formula:
centuries = days ÷ 36,525 (good for long ranges that include leap years).
For a quick estimate, use days ÷ 36,500.
Using 36,525 days per century:
10,000 ÷ 36,525 = about 0.274 centuries.
That’s a little over one-quarter of a century.
Using 36,525 days per century:
1,000 ÷ 36,525 = about 0.0274 centuries.
That’s under three-hundredths of a century.
Using 36,525 days per century:
365 ÷ 36,525 = about 0.01 centuries.
One year is about one-hundredth of a century.
Half a century is 50 years.
A quick estimate is 18,250 days (50 x 365).
With leap years included, it’s closer to 18,262 days in many 50-year spans.
A decade is 10 years and a century is 100 years.
A decade is about 3,650 days, while a century is about 36,500 days.
So a century is about 10 decades.
36,500 assumes every year has 365 days.
36,525 allows for leap years over a long time span. Most 100-year periods include about 24 or 25 leap days, so the total changes.
No. The total depends on which years you include.
Most years divisible by 4 are leap years, but years divisible by 100 are not, unless they’re also divisible by 400. That rule can change the leap-day count in some centuries.
Start with the exact dates, then count real calendar days between them.
If you only have a day count and need an estimate, days ÷ 36,525 gives a solid long-range average.
Yes. Many people use 365.25 days per year as an average that includes leap years.
That makes a century: 100 x 365.25 = 36,525 days.
Yes. A century is always 100 years by definition.
The day count changes because years don’t all have the same number of days.
For a fast estimate, divide by 36,500.
If you want a closer estimate, divide by 36,525. For many numbers, rounding the divisor to 36,500 keeps the math simple and still stays close.
The Calculate Box tool to convert days to centuries uses the open source script Convert.js to convert units of measurement. To use this tool, simply type a days value in the box and have it instantly converted to centuries.