Birthday Calculator – Find Your Age and Next Birthday
Find your age, the weekday you were born and your zodiac sign.
About the Birthday Calculator
What is the Birthday Calculator?
A birthday calculator reveals the weekday you were born on, your current age and your zodiac sign.
Why use this calculator?
It is a quick way to settle trivia, plan a birthday and check your star sign from your birth date.
How to use it
- Enter your date of birth.
- Read the weekday, age and zodiac sign.
Formula
Zodiac signs follow the tropical dates based on the day and month of birth.
Age uses today's date, so it updates automatically.
Frequently Asked Questions
How is the zodiac sign decided?
By the day and month of birth using the standard Western (tropical) date ranges, such as Leo from July 23 to August 22.
Do you store my birth date?
No. Everything runs in your browser and nothing is saved or sent anywhere.
Does it account for leap years?
Yes. The date logic follows the Gregorian calendar, including leap years and differing month lengths.
Are weekends and holidays excluded?
Only if the calculator says so. By default, results count every calendar day; use a business-day option where available.
Which time zone is used?
Calculations use whole calendar dates and are time-zone independent unless a time-of-day is involved.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.
How accurate are the results?
We use standard, widely accepted formulas and calculate in your browser using double-precision arithmetic. Results are rounded for readability, so treat them as reliable estimates rather than a guarantee. Real-world factors can vary the true figure.
Can I add this calculator to my own website?
Yes. Open this calculator page and use the "Add to your website" box in the sidebar to copy a ready-made iframe snippet, then paste it into any HTML page.
Does it work on a phone or tablet?
Yes. The layout is fully responsive, so it works on desktops, laptops, tablets and mobile phones, and every input adapts to touch screens.
Is the information I type kept private?
Yes. All calculations run locally in your browser. Nothing you enter is uploaded, stored or shared with anyone.