Birth Calculator Online

Calculate age from birth date. See exact age in years, months, days, total days and weeks.

Birth date

As of date (optional)

Leave empty for today

Birth calculator online

Use the birth calculator to work out age from a birth date. Enter the date of birth and optionally an as-of date to get age in years, months, days, total days and weeks.

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Age Calculator →Birth Date Calculator →Birthday Calculator →

Cite This Calculator

Reference this calculator on your website or in your work using the citation below:

HTML Citation Code:

<p>Calculator: <a href="https://onlinecalculator.co.uk/time/birth-calculator" target="_blank">Birth Calculator Online</a> - OnlineCalculator.co.uk</p>

APA Style Citation:

OnlineCalculator.co.uk. (2025). Birth Calculator Online. Retrieved from https://onlinecalculator.co.uk/time/birth-calculator

Note: This calculator is free to use and reference. No permission required for educational or commercial citation.