Date & Time Tools

Days Until My Birthday Calculator

How many days until your next birthday: days, weeks, the weekday it falls on, and the age you turn, with a choice for February 29 birthdays.

Half Birthday Calculator

Find your half birthday: the date six months after your birthday, the weekday it falls on, how many days away it is and the age you will be (like 37.5).

What Date Do I Turn a Certain Age? Calculator

Find the exact date you turn 18, 21, 40, 65 or any age: the date, the weekday and how many days away or ago it is.

Zodiac Sign Calculator: Find Your Sun Sign by Birthday

Find your Western zodiac (sun) sign from your birth month and day, with the date range for each of the 12 signs and a note when you are on the edge of two signs.

Chinese Zodiac Calculator: Find Your Animal Sign by Birth Date

Find your Chinese zodiac animal from your full birth date, using the real Lunar New Year date for your birth year (1901 to 2100), with the other years of your animal.

Birthstone by Month Chart

Birthstone for every month of the year, including the alternates for March, June, August, October, November and December, based on the lists published by GIA.

What Generation Am I? Birth Year Generation Calculator

Find your generation from your birth year using Pew Research Center definitions: Silent, Baby Boomer, Gen X, Millennial, Gen Z and Gen Alpha, with the year ranges.

What Year Was I Born? Birth Year From Age Calculator

Work out a birth year from an age: the two possible years, or the exact year once you add the birth month and day.

Age on Other Planets Calculator

See how old you would be on Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto, using NASA orbital periods, with the date of your next birthday on each.

Cousin Relationship Calculator: First, Second and Removed

Work out whether two people are first, second or third cousins and how many times removed, from the closest ancestor they share.

Countdown Timer

Create customizable countdown timers for any event. Track days, hours, minutes, and seconds with live updates. Share via URL with one click.

Add to Calendar Generator

Create a downloadable .ics calendar file for any event, with real RRULE recurrence support.

Unix Timestamp Converter

Convert Unix seconds or milliseconds into local and UTC dates.

Epoch to Date Converter

Convert epoch timestamps to dates, one or many at once.

Date to Epoch Converter

Turn a date and time zone into a Unix epoch timestamp.

Unix Time in Milliseconds

Current Unix ms and s, ms, us, ns conversions.

Year 2038 Problem Checker

Check if a timestamp fits in signed 32-bit time.

Excel Date to Unix Timestamp

Convert Excel serial dates to Unix time and back.

Days Since Epoch Calculator

Days since 1970-01-01 for any date, and back.

RFC 3339 Timestamp Validator

Check a date-time against RFC 3339, see the failed rule, and get UTC, epoch milliseconds and offset.

Discord Timestamp Generator

Get <t:UNIX:STYLE> codes for any date, time and zone.

Meeting Time Zone Planner

Pick 2+ cities and find the hours that work for everyone, with real DST handling.

Global Calendar Converter

Convert Gregorian dates into Japanese, Buddhist, ROC, Ethiopian, and Persian Jalali formats.

Hebrew Date Converter

Convert Gregorian dates to Hebrew dates and back, with Adar I/II and an after-sunset option.

IANA to Windows Time Zone Converter

Map IANA IDs like America/Toronto to Windows zone names and back, with territories and current UTC offsets.

Julian Date Converter

Convert dates to Julian Date, Julian Day Number, MJD and ordinal day of year, and back.

Japanese Era Converter

Convert Reiwa, Heisei, Shōwa, Taishō and Meiji dates to Gregorian dates and back.

Hijri to Gregorian Converter

Convert Hijri dates to Gregorian and back with Umm al-Qura or Islamic civil rules.

Thai Buddhist Calendar Converter

Convert Thai Buddhist Era dates to Gregorian dates and back with full date validation.

Taiwan ROC Year Converter

Convert Minguo years and full dates to Gregorian format and back.

Easter Date Calculator

Find Easter for any year, plus Good Friday, Ash Wednesday, Ascension and Pentecost.

Indian National Calendar (Saka)

Convert Gregorian dates to India's civil Saka calendar and back, including Chaitra leap-year boundaries.

Chinese Lunar to Gregorian Converter

Convert Chinese lunar dates with leap months, festival dates and zodiac year, 1901-2100.

Discord Snowflake to Date Decoder

Decode a Discord ID into its creation time, worker, process and increment, or turn a date into a snowflake.

ISO 8601 Duration Parser

Check a duration like P3Y6M4DT12H30M5S against RFC 3339, see its parts and total seconds, or build PT1H30M.

ISO Week Number Calculator

Convert a date to its ISO 8601 week date like 2026-W40-4 and back, compare ISO and US week numbers, and list a year's weeks.

Add Hours and Minutes Calculator

Add or subtract hours and minutes in any number of rows, total in h:mm and decimal

Elapsed Time Calculator

Time between two clock times, overnight or across dates, in hours and minutes

Decimal Hours to Minutes Converter

Decimal hours to h:mm and back, with a printable minutes-to-decimal chart

Day of the Year Calculator

Day number of any date, days left in the year, and day number to date

Time Card Calculator

Weekly timesheet total with unpaid breaks and optional rounding, h:mm and decimal

Daylight Saving Time Dates by Year

US and EU daylight saving start and end dates for any year

Seconds, Minutes, Hours and Days Converter

Convert any length of time between seconds, minutes, hours, days and weeks

Working Hours Until a Date Calculator

Working hours between two date-times for your work day, weekdays and days off

Ethiopian to Gregorian Converter

Convert Ethiopian dates to Gregorian and back with Amharic month names.

Business Days Calculator

Count business days between two dates, or add business days to a date. Weekdays only (Monday to Friday) — free and instant, works entirely in your browser.

Day of the Week You Were Born Calculator

Find out what day of the week any birthdate fell on. Enter a birthdate and see the exact day, calculated using the real Gregorian calendar.

Leap Year Checker

Check whether any year is a leap year under the real Gregorian rule, and see the next and previous leap years. Free, instant, and works entirely in your browser.