Calculators & guides
Free age, birthday, star sign and pet calculators
Get an immediate answer for exact age, days lived, birthday countdowns, star signs, dog years and cat years, then keep the dates that matter in LifeDates.
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Free calculator
Exact age in years, months and days
Calculate a precise calendar age on today or any comparison date.
Free calculator
How many days old am I?
Count every elapsed day and find the next thousand-day milestone.
Free calculator
Birthday countdown
See the days remaining and the age someone will turn.
Free calculator
What is my star sign?
Find the Western zodiac sign for a date of birth.
Free calculator
When is my half birthday?
Find the next date six calendar months after a birthday.
Free calculator
How long have we been together?
Calculate exact time, total days and the next anniversary.
Planet ages
How old am I on other planets?
Calculate your age and next birthday on all eight planets.
Dogs
Dog age in human years
Estimate a dog's human-age equivalent by age and size.
Cats
Cat age in human years
Understand how cats mature across their first years and beyond.
Reference
Dog age chart
Compare approximate human-age equivalents for small, medium, large and giant dogs.
Pet birthdays
Pet birthday reminders
Remember birthdays, adoption days and pet milestones on iPhone.
iPhone
Birthday reminder app
Build a reminder system for people you care about.
Widgets
Birthday widget for iPhone
Keep the next important date visible on your Home Screen.
Milestones
Life milestone tracker
Find round ages, weeks and 10,000-day celebrations.
Organise
Important dates tracker
Keep anniversaries and meaningful recurring dates together.
Pets
Life Dates Pets calculators
Choose from 12 dedicated species calculators with exact age, life stage and birthday results.
Our methods
Calculation methodology
See the rules, sources, edge cases and test examples behind every calculator.