thaitools.techPractical tools for life in Thailand
English interface

Age calculator

Calculate calendar age in years, months, days and total days.

ReviewedCheck before reuseGregorian calendar dates · Not a legal entitlement decision
Saves this tool's name on this device only (up to 20). No form values.
Only visible result text is included. Form fields are not read. Review sensitive values before sharing.

Processed locally. Results use only the displayed inputs and assumptions.

Enter values, then process to see the result.

How to use it

  1. Confirm the units and scope shown for the age calculator.
  2. Calculate calendar age in years, months, days and total days.
  3. Review the calculated result, units and rounding before using it.

Important limitation

A local utility that uses only the displayed scope and user-supplied inputs.

The interactive form is fully localized in English.

Reviewed 2026-09-16; next review 2027-03-16.

Core calculations, cited sources and main examples have been reviewed within the stated scope.

Sources

HTML Standard — DatesWHATWG · opens in a new tabSupports the stated formula and units; user inputs and prices are not verified.Source checked 2026-09-16
Recorded updates

Review history

Site changelog

Dates describe the review scope recorded below. A page update does not mean every source was checked again.

  1. Last recorded source/method review

    Core calculations, cited sources and main examples have been reviewed within the stated scope.

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