Long Island

Long Island Genealogy is a 501(c)(3) not-for-profit family organization dedicated to the distribution of free, accurate family history information.  It was created in 1993 to provide a means for Long Island family history researchers to share, exchange and connect with fellow researchers anywhere in the world.

In order for Long Island Genealogy to survive we need your support  Thanks to donations, Long Island Genealogy was able to become not-for-profit in 2017 and extend out life into the next decade!!  But that doesn’t mean we’re done.  We still need your donations to continue.  If everyone reading this chipped in we could wrap this fundraiser up in a week! But the fact is that for every 10,000 visitors only one will take the time to help.  Our only income comes from user donations.  That makes your continued support essential. Every dollar you donate is tax deductible.  If our information has been helpful to you please help us keep it accessible with a donation.

Donations can be made online through the Donate button below or by check. Please make checks payable to Long Island Genealogy, 3 Apex Dr Coram, NY 11727.
Thank you again for your continued support, and we look forward to continuing our research together in 2017 and beyond!
Birth Date Calculator
The birth date calculator is a useful tool for genealogists. It is designed to calculate the birth date when the age at death and the date of death are the only facts known. As we all know this is often the only information recorded on older headstones.

Please make entries in each box on lines 1 and 2
Use a zero where you do not have a number to enter
Item Day Month Year
Date of Death 
Age at death in Days - Months - Years
Calculated Birth Date Will Appear Here - Day - Month - Year:

To perform your calculation enter data on both lines 1 and 2 
then press this button

Note regarding Birth Date Calculator:  While doing some testing on this with 30+ death certificates already containing a birth date, death date, and age, I have found it to be only 39% accurate.  It was 1-3 days off 38.5% of the time and more than 3 days the remaining 22.5%.  No one really knows exactly how stonecutter's figured the age of the person.  Did they use a formula, count off the days between birth and death, did they figure in Leap year?  Varying methods could have been used.  A friend has a different method of calculating a birth date and running the same test, found it to be only 22.5% accurate!  These methods work ok for approximate birth dates, but it should be understood that these date's are most likely not correct.  In running a several step process from when the stonecutter first figures the age from the birth date and carves the date on the stone and then someone tries to do just the opposite, there is lots of room to make errors along the way.
Tony Bengston