# Online Calculators to Calculate time and before Dates, Days.

**Calculator explanation and how it works:** Human brains are amazingly versatile, but sometimes we find it hard to calculate in our heads. Our brain is only capable of storing so many numbers. George Miller a psychologist declared in 1950 that we can remember magical number seven plus or minus two. We can simply remember 5-9 digits before our head start to ache and forget. That’s why people started using aids to help them calculate since ancient times. The word calculator comes from the Latin word “Calculare” which means to count up using stones.

In modern words, a small hand held device that performs mathematical calculations effectively and efficiently is called calculator. There are many fields like area calculation, density calculation, exponent calculation, percent error formula, quadratic, number sequence calculators for solving mathematical calculations. **Time Duration Calculator time between two dates/times: How it works?**

The service of this calculator is to determine the exact time between any duration of number of years, months, days, hours, minutes and seconds between two moments in time. If you only need to calculate the days count without knowing hours/minutes/seconds you have to use Date Duration Calculator.

First of all we discuss how time duration calculator works: Time duration calculator finds the number of days, minutes, hours and seconds between two given points in time.

You have to fill the day, month and year fields depends upon your browser’s language. If the day, month and year are left empty the current UTC/GMT ( Coordinated Universal time (Standard time)/ Greenwich Mean time, is used as default. There are two things one is start date and end date between time duration that is considered for calculating the exact duration of time. There are few points which one should keep it mind while using time duration calculator:**Use either 24 hour format or 12 hour format.**

- Use number 1-12 for the months of year e.g. February
- Use four digits to calculate little before time duration unless you really want to calculate thousands of years back.
- Click to fill in the current time and date.
- Go to the date for only duration calculation.
- Click to fill the start of the day.
- Click to fill 12 am noon.
- Click to fill the end day, date, month, year hours, minutes, seconds and then click to calculate duration.

**Date duration calculator, calculate duration between two dates:**

This is use to calculate the day count and number of days, months, years between two specified dates. It is also used to calculate how many days old are you and the weekday you were born on. This also enables you to calculate add or subtract days, months and years to a date to calculate a future or a past date.

- This calculation is very easy you have to only fill few columns to have results:
- You have to add to or subtract from the date.
- You have to fill start date in which different columns of day, month, year to be filled.
- Then add or subtract accordance with your calculation of previous period or present one.
- And fill Years, months, weeks, days include only certain weekdays.
- Click the button to calculate new date.

This tool is useful for genealogists as sometimes they don’t have records of birth date on the death certificates or grave if one wants to know the age.

Famous scientist Albert Einstein’s birth date based on the age and death date.