Days Between Dates Calculator
Calculate the number of days between any two dates. Essential for project planning, age calculations, and countdown tracking.
Date Difference Examples
| Start Date | End Date | Days |
|---|---|---|
| Jan 1 | Dec 31 | 364 |
| Jan 1 | Jan 31 | 30 |
| Birthday | Today | Your age in days |
Implementation
``javascript
function daysBetween(date1, date2) {
const oneDay = 24 * 60 * 60 * 1000;
const d1 = new Date(date1);
const d2 = new Date(date2);
return Math.round(Math.abs((d2 - d1) / oneDay));
}
``
Including vs Excluding End Date
Some calculations include both start and end dates (inclusive), while others exclude one. Our calculator shows both counts clearly.