How to Enable Gzip Compression in WordPress

The world of website optimization, especially when speeding up WordPress, is a lot to cover. Sometimes tools in speed optimization like Gzip for WordPress, are topics that need their own articles. In this article you’ll learn how to better understand Gzip for WordPress, but also how to enable Gzip compression for WordPress.

Optimizing file sizes for quicker loading times and reducing bandwidth usage is super important for any website owner. This is where Gzip comes into the picture. Gzip is a data compression method that significantly reduces the size of files, making data transfer faster and more efficient.

Gzip, short for GNU zip, is a popular data compression algorithm developed in the early 1990s by Jean-loup Gailly and Mark Adler. The main purpose of Gzip is to reduce the size of files before they are transmitted over the internet. This compression gives faster data transfer times and reduces bandwidth usage, which is super helpful for website owners and users. A smaller file size results in web pages loading faster, as well as enhancing the overall user experience and possibly improving search engine rankings.

The Gzip compression process works by finding repeated strings or patterns of data within a file and replacing them with shorter representations. This is achieved through two primary steps: the LZ77 algorithm and Huffman coding.

The first step, the LZ77 algorithm, scans the input file and searches for repeated sequences of characters. It then creates pointers to these recurring patterns, allowing the compressor to replace the repeated data with references to its previous occurrences. By doing so, the file becomes more compact.

In the second step, Huffman coding is applied to the data. Huffman coding is a variable-length encoding technique that assigns shorter codes to more frequently occurring characters and longer codes to less frequent ones. This further reduces the size of the file by using shorter representations for common data and longer representations for less common data.

Gzip is widely used in web development to compress various file types, such as HTML, CSS, JavaScript, and JSON, among others. When a web server receives a request from a user's browser, it can check if the browser supports Gzip compression. If it does, the server compresses the requested file using Gzip before sending it over the internet. Upon receiving the compressed file, the browser then decompresses it before displaying the content to the user.

While Gzip offers significant benefits, it is worth noting that it is most effective on text-based files, such as HTML and CSS. Binary files, like images, videos, and already compressed files (e.g., JPEG or MP3), do not experience significant compression gains with Gzip and may even increase in size slightly due to overhead.

Gzip for WordPress is a powerful tool that significantly reduces the size of website files, leading to faster loading times and improved user experiences. In this article, we will explore what Gzip for WordPress is, how it works, and why it is crucial for website optimization. Gzip is a compression method that effectively reduces the size of files, such as HTML, CSS, JavaScript, and JSON, by compressing them into a smaller format.

When a user visits a WordPress website, their browser sends a request to the web server, which then responds by sending the requested files, such as HTML, CSS, and JavaScript, back to the browser. Before Gzip compression, these files are typically in their uncompressed form, resulting in larger file sizes that take longer to transfer over the internet.

Here's where Gzip for WordPress comes into play. When a web server that hosts a WordPress site is configured to use Gzip compression, it checks if the user's browser supports Gzip. If the browser supports it, the server compresses the requested files on the fly using Gzip before sending them to the user's browser. If the browser does not support Gzip, the server sends the uncompressed files as usual.

The compressed files received by the user's browser are much smaller than the original ones. As a result, the time it takes to transfer the files over the internet is significantly reduced. This leads to faster loading times for web pages, which is critical for keeping users engaged and satisfied.

The benefits of Gzip for WordPress are far-reaching. Faster loading times not only enhance the user experience but also have a positive impact on search engine rankings. Search engines like Google consider website speed as one of the ranking factors. Websites that load quickly are more likely to rank higher in search results, potentially driving more organic traffic to the site.

There are 2 methods to enable Gzip compression in WordPress:

1. Using a plugin
2. Using code

If you’re not knowledgeable in handling code, the plugin method may be best for you. With either method, before you apply any changes, make sure to backup your WordPress site.

How to Enable Gzip Compression in WordPress: Using a plugin

This method assumes that you haven’t installed a cache plugin. It’s best to make sure that you don’t already have one installed. If you do, then look through that plugin’s settings to make sure gzip compression is turned on. In some cases, you might need to look up the plugin’s documentation in order to learn how to enable Gzip compression in WordPress.

1. Log into your WordPress admin dashboard.
2. Navigate to "Plugins" in the left-hand menu and click "Add New."
3. In the search bar, type WP Super Cache.
4. Install and activate the WP Super Cache plugin.
5. Once activated, go to the plugin's Advanced tab settings, and select the box to "Compress pages so they're served more quickly to visitors."
6. Save settings.

How to Enable Gzip Compression in WordPress: Using code

This method assumes that you’re comfortable handling code, and your web host allows you to add code that will enable Gzip compression. For this tutorial, you'll either need to log into your web host and use the File manager, or use a FTP client like Filezilla to make the changes needed to enable Gzip compression in WordPress.

Step 1. Navigate to the root directory of your WordPress installation (usually named "public_html").

Step 2. In the root directory, look for a file named ".htaccess." This is a hidden file, so make sure your file manager settings show hidden files.

Step 3. Right-click on the ".htaccess" file, and select "Edit" or "Code Edit" from the context menu. Alternatively, you can download the file to your computer, edit it using a text editor, and then upload it back to the server.

Step 4. Add the following lines at the beginning of the ".htaccess" file to enable Gzip compression:

<IfModule mod_deflate.c>
  # Enable Gzip compression for commonly used file types
  AddOutputFilterByType DEFLATE text/plain
  AddOutputFilterByType DEFLATE text/html
  AddOutputFilterByType DEFLATE text/xml
  AddOutputFilterByType DEFLATE text/css
  AddOutputFilterByType DEFLATE application/xml
  AddOutputFilterByType DEFLATE application/xhtml+xml
  AddOutputFilterByType DEFLATE application/rss+xml
  AddOutputFilterByType DEFLATE application/javascript
  AddOutputFilterByType DEFLATE application/x-javascript
  AddOutputFilterByType DEFLATE application/json
</IfModule>

Step 5. Save your .htaccess file.

You may want to clear your website and browser cache after applying this code in order for it to properly take effect.

Now that you know about Gzip for WordPress, check to see if you have any caching turned on for your site. You may want to check to see if Gzip is an option in your cache plugin. If you don’t have it, use this article to help you enable Gzip compression in WordPress.