Age calculator
Calculate completed years, months and days at a reference date. Month-end anniversaries clamp to the last valid day.
Input
How to use this tool
- Enter your values or choose a local file. Replace the example data with your own.
- Review options, units and assumptions, then run the tool.
- Check the result before copying or downloading it. Keep an original copy of important files.
Method & assumptions
Calculate completed years, months and days at a reference date. Month-end anniversaries clamp to the last valid day.
completed years + calendar months + remaining daysWorked example
2000-01-01 → 2026-01-01 = 26
Limits & important notes
Dates use UTC calendar arithmetic. Weekdays exclude Saturdays and Sundays only, not holidays. Date ranges exclude the end date. Shift hours do not adjust for daylight-saving changes.
Content updated:
Privacy & Free to use
Are my inputs stored?
Your inputs stay in this tab. We do not receive your files, pasted text or calculation values.
Is this tool free?
Yes. No signup or payment is required.
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