UD5 Toolkit
Date Locale Previewer – Online Intl.DateTimeFormat Visualizer
Select a date, time zone, and locale to see how it appears in various formats (long, short, etc.). Ensure correct i18n.
Tag: Date Utilities - Calendar & Calculator
19+ toolsDay of the Week Finder – What Day Was July 4, 1776?
Enter any past or future date and instantly learn the day of the week. Uses the Zeller’s congruence algorithm for accurate results.
Roman Numeral Date Converter - Online MMXXV Style
Convert any date into Roman numerals (day‑month‑year) for tattoos or special occasions. Clean and local.
Day of Year Calculator - Online Ordinal Date
Find out what day number of the year any date is (1‑366). Also shows days remaining. Simple reference.
Leap Year Checker - Online Verify February 29
Enter a year to check if it is a leap year. Shows the rule explanation and next/previous leap years. Simple reference.
Week Number Finder - Online ISO Week of Year
Enter any date and get the ISO week number. Also shows start and end of that week. Handy for project planning.
Date to Unix Epoch Converter - Online Human to Timestamp
Convert any human‑readable date to a Unix timestamp in seconds or milliseconds. Also shows ISO 8601. Clean interface.
Countdown to Date - Online Custom Event Timer
Create a personal countdown to any future date (birthday, vacation, launch). Shows days, hours, minutes, seconds. Locally stored.
Age Calculator - Online Real-Time Age by Date of Birth
Find your exact age in years, months, and days. Calculate the time until your next birthday. All date computations are performed locally and accurately.
Average Frost Date Lookup – Online Enter Zip Code for Garden
Find average first and last frost dates for your zip code using cached NOAA data. Garden planning essential.
Elapsed Time Calculator - Online Duration Between Dates/Times
Enter two date‑time values and get the exact years, months, days, hours, minutes difference. Word output also.
Text to ISO Date Converter - Online Parse Any Date String
Paste a human‑readable date (like 'next Friday' or 'March 5, 2023') and convert it to ISO 8601 format. Quick and tolerant.
Easter Date Finder - Online Computus Algorithm for Any Year
Find the date of Easter Sunday for any given year. Learn about the computus algorithm. Simple and accurate.
Quarter of Year Finder - Online Q1 Q2 Q3 Q4 Tool
Enter any date and instantly know which quarter it belongs to. Also shows fiscal quarter if start month set.
Roman Numeral Date Converter - Online MMXXVI Style
Convert any date into Roman numerals (day‑month‑year) for tattoos or special occasions. Clean and local.
Date Duration Calculator - Online Calendar & Workdays
Calculate the exact number of days, weeks, months, and workdays between two dates. Visual calendar highlights. Perfect for projects.
Day of the Week Calculator - Online Find Weekday from Date
Find what day of the week any past or future date falls on. Uses Zeller’s congruence. Fun historical reference tool.
Unix Timestamp Converter - Online Epoch & DateTime Tool
Convert Unix timestamps to human-readable dates and vice versa. Supports seconds and milliseconds. Ideal for developers debugging time-related code.
Week Number & Start/End Dates - Online ISO 8601
Enter any date and get its ISO week number, plus the start and end dates of that week. Quick reference.