PHP - convert incorrect umlauts (utf8)

Question

how can I convert incorrect Umlauts like:

 ä <- ä
 Ä <- Ä
 ö <- ö
 Ö <- Ö
 ü <- ü
 Ü <- Ãœ
 ß <- ß
…

Thats my current Code but it is not working:

echo iconv("ISO-8859-1", "UTF-8" "Ü");

Answer 1

Try this. It outputs: äÄöÖüÜß

<?php

$inputs = [ 'ä', 'Ä', 'ö', 'Ö', 'ü', 'Ü', 'ß' ];

foreach ($inputs as $input)
{
    echo iconv('UTF-8', 'WINDOWS-1252//TRANSLIT', $input);
}