Date difference

Count elapsed calendar days between two dates in either direction.

Your dates and times stay in your browser and are not stored.

Method and assumptions

Method version 1.0.0 · Updated September 22, 2026

Elapsed days

Formula: End date − start date

Gregorian civil dates from years 0001 to 9999, without time or timezone. The same date gives 0 days; an earlier end date gives a negative result. No inclusive counting or business-day calculation. Example: February 28 to March 1, 2024 = 2 days.

start: Start date
end: End date

Gregorian calendar from years 0001 to 9999. Date, duration and rounding conventions are specified for each mode.

Calculate with code

These short examples use the same inputs and core calculation as this tool. Adapt validation and formatting to your application.

JavaScript

const days = (Date.UTC(2026, 0, 10) - Date.UTC(2026, 0, 1)) / 86_400_000;
console.log(days); // 9

TypeScript

const days: number = (Date.UTC(2026, 0, 10) - Date.UTC(2026, 0, 1)) / 86_400_000;
console.log(days); // 9

Python

from datetime import date
print((date(2026, 1, 10) - date(2026, 1, 1)).days)  # 9

Java

var start = java.time.LocalDate.of(2026, 1, 1);
var end = java.time.LocalDate.of(2026, 1, 10);
System.out.println(java.time.temporal.ChronoUnit.DAYS.between(start, end)); // 9

var start = new DateOnly(2026, 1, 1);
var end = new DateOnly(2026, 1, 10);
Console.WriteLine(end.DayNumber - start.DayNumber); // 9