⏰ 30 Calculators · 8 Topics · Updated April 2026
Time & Date Calculators
Free calculators for age, dog years, cat years, days between dates, work hours, and countdowns. Precise date math with leap year support.
Precise date calculations that account for leap years, varying month lengths, and time zones. Find your exact age, convert your pet's age to human years using modern veterinary science (not the outdated 7× rule), count days between dates, and track work hours.
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Age Calculator
Calculate your exact age in years, months, and days from your date of birth.
Dog Age Calculator
Convert your dog's age to human years using the latest veterinary science (not the outdated 7× rule).
Cat Age Calculator
Convert your cat's age to human years using current veterinary guidelines.
Days Between Dates Calculator
Calculate the number of days, weeks, and months between two dates.
Countdown Calculator
Calculate exactly how many days, hours, and minutes until a specific date or event.
Work Hours Calculator
Calculate total hours worked in a week for timesheet and payroll purposes.
Browse by Topic
Age
5 calculatorsCalculate exact age in years, months, and days. Convert dog and cat ages to human years using modern veterinary guidelines.
Age Calculator
Calculate your exact age in years, months, and days from your date of birth.
Cat Age Calculator
Convert your cat's age to human years using current veterinary guidelines.
Dog Age Calculator
Convert your dog's age to human years using the latest veterinary science (not the outdated 7× rule).
Age in Months Calculator
Exact age in months.
Time Until Retirement Calculator
Years, months, days to retirement.
Date
2 calculatorsCount the exact number of days, weeks, and months between any two dates. Create countdowns to events.
Time
1 calculatorCalculate total work hours per week for timesheets and payroll.
Duration
3 calculatorsConversion
4 calculatorsDeveloper
1 calculatorCalendar
9 calculatorsDate + Days Calculator
Add or subtract days from a date.
Business Days Calculator
Count weekdays between two dates.
Weeks Between Calculator
Weeks between any two dates.
Fraction of Year Elapsed
How much of the year is already over.
Time Zone Delta Calculator
Hours offset between two zones.
Age in Days Calculator
Total days you have been alive.
Retirement Countdown Calculator
Days/months until retirement.
Half Birthday Calculator
Your next half-birthday date.
Minutes to Hours Converter
Convert minutes into hours.
Frequently Asked Questions
How do you convert dog years to human years?
The old '7× rule' is inaccurate. Modern veterinary science says: a 1-year-old dog equals a 15-year-old human, a 2-year-old equals 24, then add 4-5 years per dog year after that for small/medium dogs. Large dogs age faster after year 2 (add 6-8 per year), and giant breeds fastest (8-10 per year).
How is exact age calculated?
We count complete years, months, and remaining days between your birth date and today, properly accounting for leap years and months with different lengths. If you were born on February 29, your age increments on March 1 in non-leap years.
How do cat years compare to dog years?
Cats age similarly to dogs in the first two years: year 1 = 15 human years, year 2 = +9 (total 24). After that, each cat year adds about 4 human years, slightly less than most dog breeds. Indoor cats typically live 13-17 years (65-80+ in human years).