One of my favorite things to do as a genealogist is to look at cemetery markers and death records. If I am lucky, I will find birth and death dates for the deceased here. Yet sometimes, especially in earlier records, I find the birth date omitted. The death record may give only the death date coupled with the age of the deceased.
I encountered this recently when I studied the church burial record for my Finnish ancestor Anders Abelsson Mattila. He had died on the 27th of April, 1882 at the age of 55 years, 5 months, and 23 days. The record did not provide a birth date for him.
In my early days of genealogy, I would have had to pursue a complicated formula to derive his birth date from the information on this record. No more. Now I can use a simple utility found on Search For Ancestors at http://www.searchforancestors.com/utility/birthday.html to calculate this date. The Tombstone Birthday Calculator on this site allows me to plug in the death date and age information, and then it calculates the birth date for me.
Using this tool, I learned that Anders was born 4 November 1826. This information exactly matches the date given on all his subsequent records. The quick answer I received from the online calculator gave me another rewarding experience analyzing a death record. You can bet I have this Calculator bookmarked as part of my genealogical tool kit.