Date & Time tools
10 free date & time tools, all running in your browser.
Age Difference Calculator
Calculate the exact age difference between two birthdays in years, months, days, and total days. Compare age gaps for couples, siblings, or friends with this free calculator.
Countdown Timer
Free online countdown timer with live display, presets, target dates, progress ring, and alarm. Perfect for meetings, workouts, events, and presentations.
ISO Week Date Converter - ISO 8601 Week Calculator
Instantly convert any Gregorian date to ISO 8601 week notation and convert ISO week dates back to calendar dates with full week ranges.
Julian Date Converter
Convert between Gregorian calendar dates and Julian Day Numbers (JD) instantly. Supports full date and time in UTC.
Lunar Age Calculator
Calculate your age based on lunar months, lunar years, and Moon cycles using your date of birth.
Next Weekday Finder
Find the next occurrence of any weekday from any start date. Calculate multiple upcoming Mondays, Tuesdays, etc. instantly.
Quarter of Year Calculator
Find which financial quarter a date falls in, with calendar and fiscal quarter ranges.
Retirement Date Calculator
Calculate your exact retirement date from birth date and desired retirement age with life expectancy projections
Roman Numeral Date Plaque
Format any date as a Roman numeral plaque for weddings, anniversaries, and engraving.
Time Since Calculator
Show exact time elapsed since any past date and time, live down to the second.