How to remove a specific part of a string

If you use PHP 5.2.0 upwards, you can use the pathinfo function with the PATHINFO_FILENAME constant, this will return only the file name. So, just concatenate .zip :

<?php
  $nome_arquivo = "Icon.png";
  $novo_nome =  pathinfo($nome_arquivo, PATHINFO_FILENAME) . '.zip';
  echo $novo_nome; // Retorna "Icon.zip"
?>

Ideone: link

For versions below, you need to use the PATHINFO_BASENAME constant, however this will return the whole file name (using the first code as an example, Icon.png ). What you can do is use preg_replace to get the filename and then concatenate .zip . Example:

<?php
  $nome_arquivo = "Icon.png";
  $arquivo = pathinfo($nome_arquivo, PATHINFO_BASENAME);
  $novo_nome = preg_replace('/(.+?)\.[^.]*$|$/', '$1', $nome_arquivo) . '.zip';
  echo $novo_nome; // Retorna "Icon.zip"
?>

Ideone: link

You can use the str_replace function, see a working example here .

<?php
    $valor = "Icon.png.zip";
    $valor = str_replace(".png", "", $valor);
    echo $valor;
?>

You can also pass an array containing the words you want to replace:

<?php
    // array com os valores que devem ser substuidos
    $ext = array(".png", ".jpg", ".gif");

    $png = "IconPNG.png.zip";
    $png = str_replace($ext, "", $png);

    $jpg = str_replace($ext, "", "IconJPG.jpg.zip");

    echo $png . "\n";
    echo $jpg;
?>

Functional example here .