Question: [This example](https://tcpdf.org/examples/example_028/) on tcpdf's website shows how to use page formats like A4, A5 etc, but how do I set tcpdf to use custom sizes like 175mm x 266 mm?

Solutions appreciated.

Answer: 
Go to /config/tcpdf\_config.php and around line 117, modify the line:

```
define ('PDF_PAGE_FORMAT', 'A4');

```

by

```
define ('PDF_PAGE_FORMAT', 'LETTER');

```

It is important to put "LETTER" in uppercase, you can see all possible values in this file: `tcpdf/include/tcpdf_static.php`.
The above answer won't work for me, so I add my solution here - from <http://www.tcpdf.org/examples/example_060.phps>, change urx, ury for your purpose

```
// set page format (read source code documentation for further information)
// MediaBox - width = urx - llx 210 (mm), height = ury - lly = 297 (mm) this is A4
$page_format = array(
    'MediaBox' => array ('llx' => 0, 'lly' => 0, 'urx' => 210, 'ury' => 297),
    //'CropBox' => array ('llx' => 0, 'lly' => 0, 'urx' => 210, 'ury' => 297),
    //'BleedBox' => array ('llx' => 5, 'lly' => 5, 'urx' => 205, 'ury' => 292),
    //'TrimBox' => array ('llx' => 10, 'lly' => 10, 'urx' => 200, 'ury' => 287),
    //'ArtBox' => array ('llx' => 15, 'lly' => 15, 'urx' => 195, 'ury' => 282),
    'Dur' => 3,
    'trans' => array(
        'D' => 1.5,
        'S' => 'Split',
        'Dm' => 'V',
        'M' => 'O'
    ),
    'Rotate' => 90,
    'PZ' => 1,
);

// Check the example n. 29 for viewer preferences

// add first page ---
$pdf->AddPage('P', $page_format, false, false);

```