Age Calculator
Calculate age in years, months, weeks, days, hours, and seconds. Discover upcoming birthdays and milestones with this precise age calculator.
Plan birthdays and milestones with confidence
Set any birth date and comparison date to see the exact time span between them. Copy the summary for forms, visa paperwork, or party invites in seconds.
Age calculator inputs
Choose two dates to calculate the exact difference.
How this age calculator works
- We subtract your birth date from the as-of date down to the day.
- The difference is converted to years, months, and days, adjusting for leap years.
- We also total the interval in weeks, hours, minutes, and seconds for extra context.
Why calculate age precisely?
- Complete paperwork that requires exact ages (school, immigration, or medical forms).
- Plan milestone parties, retirement countdowns, or baby celebrations with accurate countdowns.
- Track developmental stages for kids or highlight “1000 days” and similar social media moments.
Age milestones to watch
From newborn checkups to retirement planning, knowing the exact number of days or weeks since birth helps keep life events organized. This age calculator keeps your timeline clear, whether you are planning travel, education, or celebrations.
How It Works
The Age Calculator runs entirely in your browser using JavaScript. Unlike other tools that send your data to a server, we process everything locally on your device. This guarantees 100% privacy and blazing fast speed.
- No server interaction – data never leaves your device
- Instant results since there is no network latency
- Works offline once the page is loaded
- Free to use with no usage limits
How to Use
Enter your birth details
Use the date picker or quick-fill buttons to set your date of birth and the comparison date.
Adjust the as-of date
Calculate age today or jump ahead/back in time for milestone planning.
Review results & share
See the exact breakdown (years, months, weeks, days) plus countdown to your next birthday.
Example Usage
Use the age calculator to plan birthdays, visa paperwork, or milestone celebrations with precise numbers.
Frequently Asked Questions
How accurate is this age calculator?
Can I check future ages?
What else can I learn?
Related Tools
The Age Calculator is maintained by CodeItBro. We aim to provide the best free developer tools on the web. If you have feedback or suggestions, please visit our contact page.