Time and Date

  • Rule of 72 Doubling Time Calculator
    Use the Rule of 72 to estimate how many years it takes an investment to double at a given annual rate. Fast, free doubling time calculator.
  • Video Playback Speed Time Calculator
    Find out how long a video takes to watch at 1.25x, 1.5x, 2x or any speed. Enter the length and speed to see your watch time and time saved.
  • Years to Days Calculator
    Convert years to days instantly. Enter any number of years and get the equivalent days using the 365.25-day average year (accounts for leap years).
  • Epoch Milliseconds to Date Converter
    Convert a Unix epoch timestamp in milliseconds to a human-readable UTC date and time (ISO 8601), with year, month, day, hour, minute and second breakdown.
  • 24-Hour to 12-Hour Time Converter
    Convert military 24-hour time to standard 12-hour AM/PM format instantly. Enter the hour and minute to see the equivalent clock time.
  • What Time Will It Be in X Hours?
    Find out what time it will be in X hours from any start time. Enter a start time and number of hours to get the result in 24-hour HH:MM format.
  • EDT to PDT Converter
    Convert Eastern Daylight Time (EDT) to Pacific Daylight Time (PDT) instantly. PDT = EDT − 3 hours. Enter any hour and minute to get the exact PDT time.
  • EST to UTC Converter
    Convert Eastern Standard Time (EST) to Coordinated Universal Time (UTC) instantly. EST is UTC−5, so UTC = EST + 5 hours (mod 24).
  • IST to UTC Converter
    Convert Indian Standard Time (IST) to Coordinated Universal Time (UTC). IST is UTC+5:30, so subtract 5 hours 30 minutes to get the UTC time instantly.
  • PST to UTC Converter
    Convert Pacific Standard Time (PST) to Coordinated Universal Time (UTC). Enter an hour and minute to instantly add the +8 hour offset.
  • Age Difference Between Two People Calculator
    Find the exact age gap between two people in years, months and days. Enter both birthdays to get the precise difference and total days apart.
  • Dog Pregnancy Due Date Calculator
    Estimate your dog's whelping (due) date from the breeding date. Canine gestation averages 63 days, with a normal range of 58–68 days.
  • Gestational Age from Ultrasound Calculator
    Calculate estimated due date (EDD) and current gestational age from an ultrasound scan date and the gestational age measured at that scan.
  • What Time Was It X Hours Ago?
    Find out what time it was a given number of hours ago. Enter the current time and hours to subtract — get the past clock time and how many days back it rolls.
  • Days Until New Year's Eve Calculator
    Find out how many days are left until New Year's Eve (December 31) from any date. Shows days, weeks, and the target year instantly.
  • Days Until Super Bowl Calculator
    Count down the days until the next Super Bowl (US), held the second Sunday in February. Enter any date and get the exact days remaining.
  • 90 Day Calculator
    Add 90 days (or any number of days) to any date instantly. Find the exact future date and day of the week, with calendar leap-year handling.
  • Milestone Birthday Date Calculator
    Find the exact date and weekday of any milestone birthday — 16th, 18th, 21st, 30th, 40th, 50th and more — from a date of birth.
  • Add Days to Date Calculator
    Add or subtract any number of days from a start date to find the exact future or past date, including the day of the week. Free online date calculator.
  • Add or Subtract Hours from a Time Calculator
    Add or subtract hours from any start time and get the resulting clock time. Wraps correctly past midnight using a 24-hour, mod-1440 calculation.
  • Clock Angle Calculator
    Calculate the angle between the hour and minute hands of a clock at any time using the formula |30H − 5.5M|. Instant, accurate, with reflex angle.
  • Add Months to a Date Calculator
    Add (or subtract) any number of months to a date. Handles month-end overflow by clamping the day to the last valid day of the resulting month.
  • 24-Hour to 12-Hour Time Converter
    Convert 24-hour (military) time to 12-hour format with AM/PM instantly. Enter the hour and minute to get the correct standard clock time.
  • GMT to IST Converter
    Convert GMT to IST (India Standard Time) instantly. IST = GMT + 5:30. Enter any GMT hour and minute to get the exact India time, plus day rollover.

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