How to compare two dates

Short answer

Date objects are compared with the usual operators:

<?php
 
$deadline = new DateTimeImmutable('2025-06-01');
$now = new DateTimeImmutable('2025-05-20');
 
var_dump($now < $deadline);

Output:

bool(true)

Strings

Dates in the YYYY-MM-DD format can be compared as strings — the order matches the calendar:

<?php
 
var_dump('2025-05-20' < '2025-06-01');

Output:

bool(true)

What not to do

Strings in the DD.MM.YYYY format cannot be compared this way: the comparison goes by the first characters, that is by the day:

<?php
 
var_dump('20.05.2025' < '01.06.2025');

Output:

bool(false)