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AgeFlow — all-in-one age calculator suite

Calculate age, reverse-estimate birth years, plan birthdays, and explore milestones with calendar precision. Every tool runs in your browser with native Date and Intl—no external APIs.

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Date of birth

Calculate age on

Age: 36 years, 3 months, 12 days

Total whole days lived on that date: 13251

Popular tools

Jump into a dedicated calculator—each page is static and works offline once loaded.

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Reverse age (DOB from age)

Estimate birth year range from age on a reference date.

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Next birthday date

Calendar date of your next birthday from today.

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Days until next birthday

Countdown in whole days to your next birthday.

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Age on a future date

How old you will be on a chosen future calendar day.

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Age on a past date

How old you were on a historical calendar day.

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Total days lived

Whole days between birth date and a reference date.

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AgeFlow — all-in-one age calculator suite

Classic age calculator

Popular tools

Reverse age (DOB from age)

Next birthday date

Days until next birthday

Age on a future date

Age on a past date

Total days lived

AgeFlow — all-in-one age calculator suite

Classic age calculator

Popular tools

Reverse age (DOB from age)

Next birthday date

Days until next birthday

Age on a future date

Age on a past date

Total days lived