Free Age Calculator With Exact Years, Months, Days, Total Days and Weeks, Birth Weekday, Next Birthday, and Age Milestones
Calculate exact age locally from date of birth to any target date, with years, months, days, total days and weeks, birth weekday, next birthday and milestones.
Calculate, inspect, visualize, and export
Local history
Eight microlearning boxes
Use calendar-aware math for calendar questions
Months and years have unequal lengths, so exact calendar differences should not be reduced to a fixed number of days.
Keep time assumptions explicit
Local dates, wall-clock times, paid weeks, breaks, weekends and holidays can materially change a result.
DST can change elapsed hours
Time-zone offsets can move when daylight-saving rules change, even when the zone name stays the same.
Inclusive and exclusive counts answer different questions
Counting both endpoints is appropriate for some schedules, while elapsed duration usually excludes one endpoint.
Rounding policies belong in the model
Timecard rounding can change paid hours, so the selected interval should be visible and consistently applied.
Capacity and pay are scenario calculations
A planner or converter supports decisions, but payroll rules, contracts and local labor law may require additional logic.
Timer accuracy depends on elapsed timestamps
A robust browser timer should calculate from timestamps instead of assuming every JavaScript interval fires exactly on time.
Exports make scenarios reproducible
Saving a result table or summary helps you document assumptions and compare later runs.
Knowledge challenge
Online checklist
Related ready pages
Frequently asked questions
Is this page free to use?
Yes. No email, phone number, signup or payment is required.
Does the main calculation run locally?
Yes. The interactive calculation is designed to run in your browser.
Can I load a worked example?
Yes. Use the Load worked example button to populate a realistic scenario.
Can I export the result?
Yes. Each page provides a primary output download and a CSV report.
Should I treat this as payroll, legal or compliance advice?
No. Verify organization policies, contracts, laws and authoritative time-zone requirements where applicable.
Reference and limitations
Use these results for planning and learning. Verify payroll policies, labor rules, organizational calendars, authoritative time-zone behavior, and other domain requirements when they matter.