How do we calculate for a century?

a century is 100 years.
in the number or days is quite a headache because of the leap year problem.a century begins on 1st January * 401; 2001;
we were wrong to celebrate the new century on 1st Jan 2000!

it then lasts till 31 dec *0; eg 500;2100 etc.
the number days depends on the leap year 500 is not a leap year but 400 is.for more leap year.
lllly, 1900 ws not a leap year, but 2000 was

eg: 1st jan 401 to 31 dec 500 is one has 25 leap years
total number of days=365*100+25=36525.
1st jan 1901 to 31 dec 2100 is one century. it has 26 leap years
total number of days=356*100+26=36526.
1 century = 100 yrs.
1 century = 100
so simple first u start calculating from days
8 days 1 week
4 weeks 1 month
12 months 1 year
100 years and 1 century
now u can calculate easily
The word century has came from 'cent' which means 100.

Although in mathematics we start the numbering from '0' . Hence starting from "0" and "passing" 99 (in integers) means the century meaning when any unit reaches 100 is the century.

Be it the years (year 1 till year 100 is 1st century and on) or any scores etc.
one century = 100 years. The Latin word 'cent' means 100 as in per cent (per 100), centimetre (1/100th of a metre).
centuary means 100 years. So if you want to calculate 2 centuries i.e. 2* 100 = 200 yrs