Add, Subtract & Compare Dates
Calculate exact dates and discover the time between two dates.
Find the Difference Between Dates
Enter two dates to calculate the exact time between them.
Date Difference
The calculated time between your selected dates is:
Add or Subtract From a Date
Find a future or past date by entering a time period.
New Date Calculated
Your future or past date is shown below:
Date Tools Β· AksaOrbit
Date Calculator: Add, Subtract, and Find Days Between Any Two Dates
Do you need to know how many days are left until your birthday? Or maybe you want to find out what date it will be 90 days from today? This free online Date Calculator helps you do all of this in just a few seconds. No math, no counting on your fingers, no confusion β just type in your dates and get your answer right away.
Simple Date Math Without the Guesswork
Compare dates, add or subtract time, and plan important events with fast and easy calendar calculations.
This tool is made for everyone. Students, teachers, business owners, event planners, and even kids can use it easily. Let's see how it works.
What Is a Date Calculator?
A date calculator is a simple tool that does date math for you. Instead of counting days on a calendar by hand, you just enter the information you need, and the calculator gives you the exact answer in one click.
You can use it to:
- Find out how many days, weeks, or months are between two dates
- Add days to a date to find a future date
- Subtract days from a date to find a past date
- Plan events, deadlines, trips, or important life moments
How to Find Days Between Two Dates
This is one of the most popular uses of a date calculator. Let's say you want to know how many days are left until Eid, a wedding, or a school exam.
Here's what you do:
- Enter your Start Date, such as today or any date you choose.
- Enter your End Date, which is the date you want to count up to.
- Click Calculate.
- See your result instantly in days, weeks, months, or years.
It's that simple. No formulas to remember.
How to Add or Subtract Days From a Date
Sometimes you don't want to count between two dates. Instead, you want to know what date it will be after adding or removing some days. For example:
To use this feature:
- Pick your Start Date.
- Choose Add or Subtract.
- Enter the number of days, weeks, months, or years.
- Get your new date immediately.
This is very helpful for planning deadlines, due dates, warranty periods, or reminders.
Why People Trust Online Date Calculators
Doing date math in your head is easy to get wrong, especially with things like leap years and months that have different numbers of days. A date calculator removes all guesswork. It always follows the correct calendar rules, so your result is accurate every single time.
A Short History of the Calendar We Use Today
The calendar most of the world uses is called the Gregorian Calendar. It was introduced in 1582 to fix small errors in the older Julian calendar, which slowly drifted out of sync with the seasons over hundreds of years. The Gregorian calendar corrected this by changing how leap years are counted. Today, almost every country uses this calendar for daily life, business, and official dates β which is exactly what this tool is built around.
Learn more about the Gregorian calendar
The U.S. Naval Observatory calendar guide explains the Gregorian calendar and its leap-year rules. You can also review the official leap-year explanation for more detail about how century years are handled.
Everyday Ways to Use a Date Calculator
You might be surprised how often date math comes up in real life. Here are some common examples:
- Planning a trip β Count the days left before you travel
- Tracking a pregnancy β Add weeks to find important dates
- Business deadlines β Add working days to a contract start date
- Age calculation β Find out exactly how old someone is
- Anniversaries and birthdays β See how many days are left
- Loan or subscription periods β Find the exact end date
Tips for Getting Accurate Results
- Always double-check your start date before calculating.
- Remember that some tools count the start date as βDay 0β and others as βDay 1β β check which one you're using.
- If your date range includes February, remember leap years can change your result by one day.
- For work-related planning, check if you need calendar days or only business days.

