Age Calculator
Enter a date of birth and get the exact age in years, months and days, plus total days, weeks and the date of the next birthday.
- Free
- No sign-up
- Runs in your browser
The date you enter never leaves your browser.
How to use Age Calculator
- Pick the date of birth (and an “as of” date if you want a past or future point).
- The age updates automatically.
- The result breaks your age down precisely, and updates the moment you change a date.
- Use the “as of” date to compute age at any past or future point, not just today.
About this tool
The calculator counts full years, months and days between two dates, and also shows the age as total days and weeks — useful for forms that ask for age in specific units.
When to use it: birthdays, anniversaries, eligibility dates and exact age in years, months and days.
Frequently asked questions
Why does the “as of” date matter?
By default the age is calculated as of today. Choosing another date lets you find someone’s age at a specific moment, such as a cut-off date.
How are leap years handled?
Exactly — the tool counts by real calendar dates, so years, months and days come out right across leap years automatically.
Why do the “months” in the result vary in length?
Because real months do. The breakdown follows actual calendar month boundaries rather than assuming 30-day months.
Can I use it for events and objects, not people?
Of course — any start date works: a company founding, a pet’s birthday, a project anniversary or a relationship milestone.
Is my date of birth stored?
No — the calculation runs on the page and nothing is saved or transmitted.
What is the difference between age in years and total days?
Years follow the calendar, while total days is the raw span — useful for “10,000 days old” style milestones.
Related tools
How to use Age Calculator
Enter the required values into the Age Calculator fields. The calculation updates as you adjust inputs. Use the result for planning, comparison, or documentation.
Practical benefits
- Complete tasks faster without installing additional software.
- Keep files private since processing happens in your browser.
- Produce consistent results that integrate into your workflow.
Frequently asked questions
Is this tool free to use?
Yes. Age Calculator is fully free with no account or subscription required.
Does it upload my files?
No. All processing occurs locally within your browser session.
Can I use this for professional projects?
Yes, the tool is designed for both casual and professional use. Always verify critical outputs.