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Age Calculator
Find your exact age in years, months, and days from your birth date.
Open toolDays Between Dates
Calculate the exact number of days, weeks, or months between two dates.
Open toolCountdown Timer
Count down to any future date and time — birthdays, holidays, deadlines.
Open toolAdd/Subtract Days
Add or subtract days, weeks, months, or years from any date.
Open toolDay of the Week Finder
Find out what day of the week any past or future date falls on.
Open toolWorkday Calculator
Count business days between dates, excluding weekends.
Open toolLearn the math behind the tools
Curious how these calculators actually work? Our Complete Guide to Calculating Dates by Hand walks through the calendar logic behind age calculation, day counting, business days, and more.
Why DateTools Hub?
All calculators run instantly in your browser — no ads blocking the tool, no account needed, no data sent anywhere. Bookmark this page for quick access whenever you need to work with dates.
Date math shows up more often than people expect: figuring out an exact age for a form, counting business days to promise a delivery date, checking what weekday a historical event happened on, or timing a countdown to a big event. Doing this by hand means tracking leap years, variable month lengths, and weekday offsets — small details that are easy to get wrong. DateTools Hub handles that arithmetic instantly and precisely, so you get a reliable answer without opening a spreadsheet or counting on your fingers.
Frequently asked questions
Are these tools really free to use?
Yes — every calculator on this site is free, requires no sign-up, and runs entirely in your browser.
Is my data stored or sent anywhere?
No. All calculations happen locally on your device using JavaScript; nothing you type is transmitted to a server.
Which tool should I use to check business-day deadlines?
Use the Workday Calculator — it counts only Monday–Friday days between two dates, excluding weekends.