The total number of days between Friday, May 5th, 1978 and Wednesday, September 12th, 1990 is 4,513 days.
This is equal to 12 years, 4 months, and 7 days.
This does not include the end date, so it's accurate if you're measuring your age in days, or the total days between the start and end date. But if you want the duration of an event that includes both the starting date and the ending date, then it would actually be 4,514 days.
If you're counting workdays or weekends, there are 3,223 weekdays and 1,290 weekend days.
If you include the end date of Sep 12, 1990 which is a Wednesday, then there would be 3,224 weekdays and 1,290 weekend days including both the starting Friday and the ending Wednesday.
4,513 days is equal to 644 weeks and 5 days.
The total time span from 1978-05-05 to 1990-09-12 is 108,312 hours.
This is equivalent to 6,498,720 minutes.
You can also convert 4,513 days to 389,923,200 seconds.
May 5th, 1978 is a Friday. It is the 125th day of the year, and in the 18th week of the year (assuming each week starts on a Monday), or the 2nd quarter of the year. There are 31 days in this month. 1978 is not a leap year, so there are 365 days in this year. The short form for this date is 5/5/1978.
September 12th, 1990 is a Wednesday. It is the 255th day of the year, and in the 37th week of the year (assuming each week starts on a Monday), or the 3rd quarter of the year. There are 30 days in this month. 1990 is not a leap year, so there are 365 days in this year. The short form for this date used in the United States is 9/12/1990, and almost everywhere else in the world it's 12/9/1990.
This site provides an online date calculator to help you find the difference in the number of days between any two calendar dates. Simply enter the start and end date to calculate the duration of any event. You can also use this tool to determine how many days have passed since your birthday, or measure the amount of time until your baby's due date. The calculations use the Gregorian calendar, which was created in 1582 and later adopted in 1752 by Britain and the eastern part of what is now the United States. For best results, use dates after 1752 or verify any data if you are doing genealogy research. Historical calendars have many variations, including the ancient Roman calendar and the Julian calendar. Leap years are used to match the calendar year with the astronomical year. If you're trying to figure out the date that occurs in X days from today, switch to the Days From Now calculator instead.