Genealogy Calculators
Practical online tools for dating records and determining relationships
The calculators are precise to the input they're given, and no further. Enter two full dates and the answer is one exact date. Enter a year where the day is unknown, and the answer is the full range of possibilities rather than a single date the record never supplied. A gravestone age becomes a twelve-month window; a census age becomes the two calendar years the birth could fall in. The range is the honest answer, and it narrows as the evidence does.
Three facts — birth, death, and age. Enter any two and get the third.
Cousin Relationship CalculatorWork out how two people are related through a shared ancestor — second cousins, first cousins once removed, and more — or look up a relationship in the chart.
Date ConverterConvert a date between the Julian and Gregorian calendars, from an Old Style year to the year from 1 January, or back — and read a Quaker numbered-month date. Adoption dates by country included.
Roman Numeral ConverterConvert Roman numerals to Arabic numbers and back — for gravestones, old documents, and record dates.
Perpetual CalendarFind the day of the week for any date on the Gregorian calendar, with a full month view for each year — useful for dating old records and events.
Census Age CalculatorTurn an age recorded in a census into the range of years the person was born.