Age Calculator

Use this free age calculator to find age on any date, total days lived, next birthday, and days until the next birthday.

All tools
Research-backed assumptions Formula steps Examples included Private in-browser use
Calendar age26 years, 3 months, 28 days

Jan 1, 2000 to Apr 29, 2026

Total days
9615
Next birthday
Jan 1, 2027
Days until next birthday
247

Formula steps

  1. Compare the birth date with the selected as-of date.
  2. Subtract full years first, then remaining full months, then remaining days.
  3. Count total days separately using UTC calendar dates.

How to use the age calculator

  1. Enter the requested dates, times, grades, dimensions, network values, password options, or units.
  2. Check the assumptions shown on the page, especially school scales, payroll rules, concrete waste, subnet type, or security handling.
  3. Press the calculate button to see the answer, supporting metrics, and formula steps.
  4. Use examples, recent answers, or copy the result while keeping the estimate limits in mind.

Common uses

Find exact age today or on a future date.

Calculate age for forms, school records, birthday planning, or quick checks.

See total days lived and days until the next birthday.

Compare leap-day birthdays with normal calendar dates.

Examples

Born Jan 1, 2000 2000-01-01 to 2026-04-29

26 years, 3 months, 28 days

Leap day birthday 2004-02-29 to 2026-04-29

Leap-aware calendar age

Birthday today 2010-04-29 to 2026-04-29

16 years, 0 months, 0 days

Frequently asked questions

Quick answers about formulas, inputs, assumptions, examples, copying, and private in-browser use.

What can I use the Age Calculator for?

Use it for quick everyday planning, school work, technical checks, or comparison tasks when the inputs match the tool page.

How does the Age Calculator calculate the result?

The calculator compares two valid calendar dates, subtracts full years, then remaining months and days. It also counts total days using UTC calendar dates.

What should I double-check before using the answer?

Check the as-of date carefully. Legal, school, insurance, and age-restricted decisions can use their own cutoff rules.

Are my inputs private?

Yes. The calculator runs in your browser tab. Recent answers stay only on the page while you use it and are not sent to a server.

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