Time and Date calculators help you work with days, dates, and durations — count the days between two dates, add or subtract time, convert time zones, and read lunar or perpetual calendars. Popular tools include the Date Duration Calculator, Date Calculator, Lunar Calendar Converter, UTC to PST Converter, and Decimal Hours to HH:MM Calculator.
Choose a tool below for an instant answer, or open the Trending tab to see what's in demand this week. Every calculator is free and works on any device.
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Days Until Easter Monday CalculatorCount the days until Memorial Day (US) — the last Monday of May. Enter a year and start date to see days remaining and the exact holiday date.
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Fortnight to Hours CalculatorConvert days into total hours instantly. Enter days plus optional extra hours to get the exact number of hours and minutes using Hours = days × 24.
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Due Date CalculatorCalculate your due date accurately with this due date calculator. Input your last period and cycle length to determine your expected delivery date. Plan for your baby's arrival with precision.
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UTC to EST ConverterConvert UTC to EST (UTC-5) instantly. Enter any UTC hour and minute to get the exact Eastern Standard Time, with a clear next/previous day indicator. Try it now.
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Hours Between Two Times CalculatorCalculate the number of hours and minutes between two times. Handles overnight spans (end before start) by wrapping to a 24-hour clock.
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Sunrise, Sunset and Solar Transit Table CalculatorBuild a daily table of sunrise, solar noon (transit) and sunset times for any latitude/longitude and UTC offset over 1 week to 2 months, using the NOAA sunrise equation.
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Epoch Seconds to Human Date CalculatorConvert a Unix timestamp (epoch seconds) into a human-readable UTC date and time, with ISO 8601 output and full year/month/day/hour breakdown.
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Day of the Week CalculatorFind out what day of the week any date falls on using Zeller's congruence. Enter year, month and day to get the weekday instantly.
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Days Until School Starts CalculatorCount down the days until the first day of school. Enter today's date and your school start date to see days and weeks remaining.
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Current Unix Timestamp CalculatorConvert milliseconds to a Unix timestamp (epoch seconds). Get the current epoch now plus minutes, hours, and days since Jan 1, 1970 UTC.
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Days Until Labor Day Calculator (US)Count the days until the next US Labor Day (first Monday of September) from any date. Auto-rolls to next year once Labor Day has passed.
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Average Speed from Time and Distance CalculatorCalculate average speed from distance and time. Enter distance in km, miles, or meters plus hours, minutes, and seconds to get km/h, mph, and m/s.
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Dog Age in Human Years CalculatorConvert your dog's age into human years using the science-based logarithmic formula (16·ln(age)+31), with a linear puppy approximation under 1 year.
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UTC Time ConverterCalculate UTC time effortlessly with UTC Time Converter. Input local time, select time zone from options, and instantly convert to Coordinated Universal Time (UTC). Simplify global time coordination now!
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Time CalculatorCalculate time intervals easily with this Time Calculator. Add or subtract days, hours, minutes, and seconds to get precise results for your time-related calculations.
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Minutes to Hours CalculatorConvert minutes to hours instantly. Enter any number of minutes and get the exact decimal hours plus an hours-and-minutes breakdown.
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HH:MM:SS to Hours, Minutes, Seconds ConverterConvert a HH:MM:SS duration into total hours, minutes, or seconds. Supports decimals, values over 59, and negative durations. Free online time converter.
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Date ± Calendar Units CalculatorAdd or subtract days, weeks, months, quarters or years from any date. Returns the new calendar date, weekday and day-of-year. Gregorian, works worldwide.
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Weekly Time Card CalculatorAdd up your weekly work hours from daily clock-in/clock-out times and breaks. Handles overnight shifts and splits regular vs overtime hours over 40.
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Minutes Per Mile to MPH CalculatorConvert your running or walking pace in minutes per mile to speed in miles per hour (mph). Enter minutes and seconds to get instant mph and km/h.
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Decimal Hours to HH:MM CalculatorConvert decimal hours to hours and minutes (HH:MM) instantly. Enter a value like 2.75 to get 2h 45m. Free, accurate decimal time converter.
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Time Between Now and Future Date CalculatorCalculate the exact time between now and a future date and time — total days, hours, minutes and seconds plus a clean day/hour/minute/second breakdown.
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Time From Speed and Distance CalculatorCalculate how long a trip takes from distance and speed. Enter distance and speed (km/h or mph) to get travel time in hours, minutes, and seconds.
Frequently asked questions
What can I do with time and date calculators?
Find the number of days, weeks, or months between two dates; add or subtract a duration from a date; convert between time zones; work out ages and countdowns; and read lunar or perpetual calendars.
Do these handle time zones and daylight saving?
Time-zone converters use standard offsets; where daylight saving applies, check that your chosen date falls inside the DST period, since local rules change through the year.
Are they free and mobile-friendly?
Yes — free, no sign-up, and they work on any device.
How accurate are the date calculations?
Date math follows the standard calendar, including leap years. For legal or contractual deadlines, confirm the count against the specific rules that apply to you.
Which time and date tools are most popular?
This page lists them by usage, most popular first; the Trending tab shows what's rising this week.
