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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Lunar Calendar ConverterCalculate Lunar Calendar dates with this easy-to-use Lunar Calendar Converter. Input any Gregorian date and instantly get its corresponding Lunar date. Accurate and fast conversion for cultural events and traditional celebrations.
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Date CalculatorCalculate dates easily with this Date Calculator. Input start date, select month options, and add or subtract days. Find precise future or past dates for planning and scheduling.
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Date Duration CalculatorCalculate the exact duration between two dates with this Date Duration Calculator. Input start and end dates to instantly determine the time span in years, months, weeks, and days.
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Army ETS Date CalculatorEstimate your US Army ETS date from your enlistment date and contract length. See days remaining, time in service, and percent of contract complete.
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Age CalculatorEnter your date of birth to get your age in years, months, and days, see the date span from birth to today, and days until your next birthday.
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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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Date & Time Duration CalculatorCalculate the exact duration between two dates and times with this Date & Time Duration Calculator. Input start and end dates/times to find precise intervals for project planning, billing, or event scheduling.
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Time Duration CalculatorCalculate time duration quickly and accurately with this Time Duration Calculator. Input start and end times to find the exact interval between two points in time.
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Julian–Gregorian Calendar Date Conversion CalculatorConvert any date between the proleptic Julian and Gregorian calendars via the Julian Day Number. Supports AD/CE and BC/BCE eras with exact integer math.
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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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UTC to IST ConverterCalculate UTC to IST time conversion instantly with this UTC to IST Converter. Input UTC time and get accurate Indian Standard Time (IST) results for seamless global time coordination.
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Shift Length CalculatorCalculate how many hours you worked in a shift from start and end times minus your unpaid break. Handles overnight shifts that cross midnight.
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Time Zone ConverterCalculate time differences across the globe with this Time Zone Converter. Easily compare multiple time zones, plan international calls, and avoid scheduling conflicts for seamless global communication.
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Hijri Date ConverterEnter a Gregorian date to convert to the Islamic (Hijri) calendar and instantly see the Hijri date, year, month, and day.
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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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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.
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.
