Master PDF Generation in PHP with mPDF: Installation, Features, and Code Samples

Overview

mPDF is a powerful PHP library that converts UTF-8 encoded HTML into PDF files. Developed by Lan Back and released under GNU GPL v2, it builds on FPDF and HTML2FPDF and is widely used for PDF generation in PHP projects.

Features

Advanced CSS support : most CSS properties are handled.

Images and HTML content : embed images and HTML directly.

Multi‑column layout : create newspaper‑style columns.

Form creation : generate and process PDF forms.

Watermarks and backgrounds : add page watermarks and background images.

System Requirements

PHP 5.6–7.2 for mPDF 7.0; PHP 7.3+ also supported.

Required extensions: mbstring and gd.

Optional extensions for advanced features: zlib, bcmath, xml, etc.

Installation

composer require mpdf/mpdf

Basic Usage

<?php
require_once __DIR__ . '/vendor/autoload.php';
$mpdf = new \Mpdf\Mpdf();
$mpdf->WriteHTML('<h1>Hello world!</h1>');
$mpdf->Output();

This outputs a PDF with Content‑Type application/pdf.

Using an HTML file

<?php
declare(strict_types=1);
use Mpdf\Mpdf;
use Mpdf\Output\Destination;
require_once __DIR__ . '/../vendor/autoload.php';
$html = file_get_contents('./pdf01.html');
$mpdf = new Mpdf();
$mpdf->WriteHTML($html);
$mpdf->Output('./pdf01.pdf', Destination::FILE);

Handling Chinese characters and symbols

$mpdf = new Mpdf([
    'autoScriptToLang' => true,
    'autoLangToFont'   => true,
    'useSubstitutions' => true,
]);

After enabling these options the output renders correctly.

Setting font and page size

$mpdf = new Mpdf([
    'autoScriptToLang' => true,
    'autoLangToFont'   => true,
    'useSubstitutions' => true,
    'mode'             => 'UTF-8',
    'format'           => 'A4',
    'default_font_size'=> 16,
    'default_font'     => '宋体',
]);

Using a PHP template

<?php
declare(strict_types=1);
use Mpdf\Mpdf;
use Mpdf\Output\Destination;
require_once __DIR__ . '/../vendor/autoload.php';
$template = file_get_contents('./pdf03.html');
$search  = ['{%username%}', '{%age%}', '{%address%}'];
$replace = ['Tinywan', date('Y-m-d H:i:s'), '浙江省杭州市西湖区梦想小镇'];
$html = str_replace($search, $replace, $template);
$mpdf = new Mpdf([
    'autoScriptToLang' => true,
    'autoLangToFont'   => true,
    'useSubstitutions' => true,
    'format'           => 'A4',
    'default_font_size'=> 14,
    'default_font'     => '宋体',
]);
$mpdf->WriteHTML($html);
$mpdf->Output('./pdf03.pdf', Destination::FILE);

Conclusion

mPDF offers a comprehensive set of features for PHP developers needing PDF output. While its CSS support may lag behind newer tools, its stability and rich functionality make it a solid choice for server‑side PDF generation.