Your life, counted in seconds, weeks or years.
Your age is more than a number of years. RelativeAge counts it in whatever unit you choose, from your date of birth.
In development Android Free
Enter your date of birth and discover your age in four different ways, just like in the app.
With the time, your Chinese age and the planets' positions are more accurate. Everything is calculated in your browser: nothing is sent or stored.
You have lived
Enter your date of birth to start.
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The Chinese calendar is lunisolar: months follow the Moon (29 or 30 days) and some years have an extra month, so Chinese New Year falls on a different date each year, between 21 January and 20 February.
The traditional age, xūsuì (虚岁), follows two rules:
That's why it is usually 1 year more than your Western age, and 2 years more between Chinese New Year and your birthday. People born in January or February before Chinese New Year belong to the previous lunar year.
It's a cultural tradition: in China the official age is calculated the same way as in the West.
Enter your date of birth to start.
Calculated with your age today. Equivalent ages are approximations: each species ages at its own pace.
Epigenetic formula (Labradors)
Wang et al., 2020: chemical changes in the DNA of 104 dogs, almost all Labradors. It may differ in other breeds.
Veterinary table by size
Table widely used in veterinary practice (attributed to the AAHA). Large dogs age faster.
AAHA/AAFP feline guidelines table
2021 veterinary guidelines: the first year equals 15 human years, the second 24, and then 4 per year.
Universal mammalian clock
Lu et al., 2023: compares species by their sexual maturity and gestation (DNA from 185 mammals).
A sample of the 81 species the app compares.
The app has all 81 species, with search and group filters, and an explanation of why some animals age faster than others.
Lifespan, maturity and gestation data: AnAge – Human Ageing Genomic Resources (CC BY 3.0).
Enter your date of birth to start.
Each planet's position is obtained by solving Kepler's equation with the orbital elements published by NASA's Jet Propulsion Laboratory (JPL), which follow from Newton's laws of motion and universal gravitation. Between 1800 and 2050 they are accurate to a fraction of a degree. NASA's high-precision ephemerides also include the small corrections predicted by Einstein's general relativity.
Your age in seconds, minutes, weeks, months or years.
Your data stays with you if you change phones.
In Spanish, Catalan and English.
You can delete your account at any time.
Free, no ads. Choose your store:
Nothing. RelativeAge will be free.
So your date of birth stays with you if you change phones.
Your email, your name and your date and time of birth, in Firebase, within the European Union.
Spanish, Catalan and English.
In the app, under Settings > Delete account, or by writing to us. It's explained on the "Delete account" page.
The Android version is in development. It will be free.
