<?php
$today = new DateTime();
$jan1 = new DateTime('January 1');
$jan1->modify('+1 year');
$days = $today->diff($jan1)->days;
echo "$days days until January 1\n";
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0
25 days until January 1