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)
Adding (or subtracting) days from a date involves determining a new date exactly N days before or after a reference date by traversing the calendar day by day.
This type of calculation is used to predict a deadline, estimate a delay, or measure a duration expressed in days.
Example: Calculate a countdown to an event (135 days before the next Olympic Games)
How to add/remove days to a date?
To add or remove days from a date, position the original date (day, month, year) in a reference calendar, then advance or rewind one day as many times as needed until the desired number of days is reached.
Date calculation tools like dCode use calendar algorithms that account for the actual length of months, leap years, and calendar transitions.
Example: Calculate the date of a 10,000-day birthday by adding 10,000 days to the birth date.
The calculation is based on the modern Gregorian calendar. For older dates (before 1582), some tools use the Julian calendar, noting that the transition from the Julian to the Gregorian calendar occurred at different times in different countries.
Approximations can only be used for estimating durations:
— 1 week = 7 days
— 1 month ≈ 30.44 days (average)
— 1 quarter ≈ 91.31 days (average)
— 1 year ≈ 365.2422 days (mean tropical year)
However, these values do not allow for the calculation of a precise date.
How to calculate your age in days?
To calculate an age in days, subtract a reference date (usually today) from the date of birth.
dCode offers a tool for calculating the difference between two dates.
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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