Tool to make calculation with dates. Date can be computed with additions or subtractions of days, weeks, months or years with a given date.
Calculation with Dates - dCode
Tag(s) : Date and Time
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Calculation with Dates
Addition of days to a given date calculator
Subtraction of days to a given date calculator
Number of days since a date
Answers to Questions (FAQ)
What is the addition of days to a date? (Definition)
The calculation of addition or subtraction of a number of days N to a given date makes it possible to define another date, in the future (or the past) located at an interval of N days.
It is very used for countdowns before an event, or to calculate an age in number of days.
Example: 135 days before the next Olympic Games
How to add/remove days to a date?
dCode locate the day, month and year in a reference calendar and add or subtract the number of days required for the initial date to calculate the new date.
Example: To determine when somebody had/will have 10,000 days, add 10000 days to the date of birth.
Calculation uses the Gregorian Calendar and the Julian one before 1582.
It is possible to get good approximations using the values: 1 week = 7 days, 1 month = 30.4 days (average value), 1 trimester = 91.3 days (average value), 1 year = 365.24 days (average value)
How to calculate your age in days?
To know how many days somebody has, use the difference between two dates tool and enter the birth date and today as the reference date for subtraction.
How to add days of months in Excel
To add days in Excel, add an integer to a date.
Example: 2010/01/01 + 1 = 2010/01/02
To add months, use the function EDATE
Example: EDATE("01/01/2010",1) = 2010/02/01
Source code
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Calculation with Dates on dCode.fr [online website], retrieved on 2022-09-30,
