How Age Works for a February 29 Birthday

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A leap-day birthday still advances one completed year each year, but the civil observance in a common year can depend on jurisdiction or purpose.

Calendar calculation

For elapsed age, calculate from the actual February 29 birth date to the reference date. Do not replace the interval with 365-day blocks.

Do not use a general calculator as the final authority for statutory age thresholds. Check the governing jurisdiction.

Enter the real dates in the How Old Am I Calculator.

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