Browse 21 free calculators in the Date & Time category.
Age Calculator - How old are you - in years, months, days, or even hours? Enter your date of birth and get your exact age, zodiac sign, Chinese zodiac animal, and the number of days until your next birthday.
Date Difference Calculator - Three modes, one tool: find the gap between two dates in years, months, weeks and days - or add and subtract days from any date. Optionally include hours and minutes for precision.
Date Calculator - Pick a date, add 90 days, get the answer. Works with days, weeks, months, and years - forward or backward. Shows the resulting date, day of the week, and a breakdown of elapsed time.
Day Counter - How many days until your vacation, wedding, or exam? Set a target date and get a live countdown - or pick a past event and see exactly how long ago it happened. Breaks every gap into years, months, weeks, days, hours, and seconds.
Time Sum Calculator - Need the total of several time entries? Type up to five durations in HH:MM format and get the sum as hours:minutes:seconds, decimal hours, and total minutes - all at once.
Time Difference Calculator - Two clock readings, one answer. Enter a start time and an end time, and the calculator returns the gap in HH:MM:SS, decimal hours, and total minutes. Handles overnight shifts that cross midnight.
Minutes to Hours Converter - How many hours is 180 minutes? Convert any number of minutes to HH:MM format or reverse - hours and minutes back to total minutes. Two modes, one click.
Leap Year Calculator - Three rules decide whether a year has 366 days. Enter any year to check, list all leap years in a range, or find the nearest leap year from a reference point.
Day of Year Calculator - January 1 is day 1. December 31 is day 365 - or 366 in a leap year. Enter a date to find its ordinal number, or enter a day number to find the date. ISO 8601 format included.
Duration Calculator - How long is the gap between 08:30 and 17:15? This calculator takes two clock times and returns the duration in hours, minutes, seconds and decimal format. Handles overnight spans across midnight.
Time Zone Difference - Night shift ends at 06:00, started at 22:00 - how many hours was that? Enter two clock times and get the absolute difference in hours, minutes, seconds and decimal format. Works across midnight.
Weeks Calculator - Pregnancy is 40 weeks. A school semester is roughly 16. A 12-week fitness plan starts on March 3 - when does it end? Enter two dates and get the exact count in weeks and leftover days.
Time Format Converter (24h / 12h) - Your flight departs at 17:45 - is that morning or evening? Convert any clock time between 24-hour format (14:30) and 12-hour AM/PM (2:30 PM). Handles midnight, noon and every edge case.
Decimal Time Converter - Payroll says 8.75, your clock says 8:45 - same thing, different format. This converter translates HH:MM into decimal hours and decimal back into HH:MM. Built for timesheets, invoicing and billing.
Day of Week Calculator - July 20, 1969 was a Sunday. December 25, 2030 falls on a Wednesday. Enter any date and this calculator tells you the weekday, day-of-year number and week number. Works for past and future dates.
Hours Calculator - Three tools in one: calculate work hours from clock-in to clock-out (with breaks), convert hours into days, weeks or months, and estimate gross earnings from hours worked and an hourly rate.
Business Days Calculator - A contract says "within 30 business days" - but which 30? Enter two dates and this calculator counts only working days, skipping weekends and optionally US federal holidays.
Months Calculator - Not every month has the same length, so counting months between two dates takes more than simple subtraction. Enter a start and end date - get the exact difference in years, months and days, plus total months, weeks and days.
Birthday Calculator - How many days until your next birthday? Find out your birth weekday, exact age in years, months and days, total days alive, and milestone anniversaries from 18 to 100.
Anniversary Calculator - Counting days, naming milestones, tracking time since any date. Enter a wedding, relationship or work anniversary and get a countdown, traditional names (Paper through Diamond) and a full timeline.
Timezone Converter - 31 time zones, instant conversion, DST-aware. Pick a date, time and source zone, choose the target zone, and get the converted result with the exact hour difference.