Interactive tool
Age Calculator
Use this tool to calculate exact time between two dates. You can also create a shareable link with your calculation results.
Genealogy use
How an age calculator helps with family history research
An age calculator is useful in genealogy because historical records often give ages instead of exact birth dates. Census records, marriage records, military records, immigration documents, and death certificates may describe a person as a certain number of years, months, or days old on a specific date.
By calculating the age between two dates, you can estimate whether a record likely belongs to the same person, check whether dates are realistic, and compare conflicting information across different sources.
Common uses
When to use this age calculator
Check census records
Use the calculator to compare a listed census age against a known or estimated birth date.
Verify death records
Death certificates often include exact age at death. Calculating backward can help estimate a likely birth date.
Compare conflicting records
When two records show different ages, calculating the date difference can help identify which record is more plausible.
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