All Date & Age Calculators
Browse our complete directory of 24 free, verified online date, day, age, time difference, and countdown calculators.
Age Calculator
Determine precise chronological age from date of birth to today or any custom target date, including upcoming birthday countdowns and total hours lived.
Date Difference Calculator
Find the exact span between two calendar dates in years, months, days, weeks, hours, and minutes with inclusive or exclusive end-date toggles.
Birthday Countdown
Real-time ticking birthday countdown showing exact time remaining until your special day, upcoming age milestone, and the day of the week it falls on.
Working Days Calculator
Determine net business and working days between any start and end date with customizable weekend patterns and specific public holiday exclusions.
Business Days Calculator
Calculate target delivery dates, service level agreements (SLAs), and project milestones by adding or subtracting a specific count of business days.
Days Between Two Dates
Fast, clean, and unambiguous day counter showing the exact number of days, weekend counts, and percentage of year elapsed between two dates.
Add Days to Date Calculator
Determine the exact future calendar date by adding specific numbers of days, weeks, months, or years with options to bypass weekends.
Subtract Days From Date
Calculate past historical calendar dates by subtracting days, weeks, months, or years from any specified reference date.
Date Duration Calculator
Convert any time interval between two dates into comprehensive multi-unit durations: years, months, weeks, days, hours, minutes, and seconds.
Week Calculator
Calculate the exact ISO week number for any date, find Monday-to-Sunday date ranges for any week, and inspect total weeks in a year.
Month Calculator
Accurately add or subtract months from dates, calculate completed month intervals, and safely handle edge cases like January 31st.
Year Difference Calculator
Measure the exact time span between two years or dates in completed full years, residual months and days, and fractional decimal years.
Leap Year Checker
Instantly verify whether any given year is a leap year (366 days) or common year (365 days) with full rule explanations and adjacent leap year lists.
Day of the Week Calculator
Discover what day of the week (Monday through Sunday) any historical event occurred on, or what weekday future milestones will land on.
Retirement Date Calculator
Estimate your exact retirement target date, remaining working years, months, and days based on your date of birth and target retirement age.
School Admission Age Calculator
Determine a child’s exact age on specific school enrollment cutoff dates (e.g. Sept 1, Dec 31) and verify grade admission eligibility.
Pregnancy Due-Date Calculator
Calculate your estimated delivery date (EDD), current gestational week and day, and trimester milestones based on LMP or conception date.
Anniversary Countdown
Live real-time countdown to your next wedding or relationship anniversary with completed years celebrated and traditional/modern milestone gift themes.
Holiday Countdown
Track live real-time countdowns to New Year’s Day, Halloween, Christmas, Thanksgiving, Valentine’s Day, or any custom holiday date.
Hours Between Two Dates
Compute the exact number of hours and decimal fractions between any two calendar timestamps with timezone considerations.
Minutes Between Two Dates
Find the precise number of minutes, seconds, and human-readable time spans between two dates and times.
Weekend Days Calculator
Calculate the exact number of weekend days (Saturdays and Sundays or custom weekend patterns) between two calendar dates.
Next Birthday Age Calculator
Find out exactly how old you will turn on your next birthday, days remaining, and what day of the week your birthday will fall on for the next 5 years.
Date Format Converter
Transform dates across DD/MM/YYYY, MM/DD/YYYY, YYYY-MM-DD, ISO 8601, Julian days, and Unix timestamps with ambiguity protection.