Browser Caching: Improve the Performance of Your Website

Website optimization is a never-ending process. There is always something you can improve. An important topic that is often neglected is improving loading speed. A simple and effective method to improve your website's loading time is browser caching. You've never heard of it? No problem! In this article we explain what browser caching is, what benefits it has, how it works, how to set it up in WordPress, and much more.

What is Browser Caching?

Every common web browser has a so-called "cache". It stores temporary copies of files from visited websites, such as CSS, JavaScript, images, and other resources needed for displaying a webpage. These temporary copies are stored in a special storage area on the visitor's device. This is supposed to reduce the loading time of webpages . When people visit a webpage, the browser usually has to download a lot of data from the server to display the page. Caching stores most of these contents locally on the device. When the page is visited again, the stored data can be accessed, significantly reducing the loading time of the webpage. The caching is done automatically or depends on the settings of the visited webpage.

Why is Browser Caching Needed?

Browser caching is needed to load webpages faster and reduce server load by caching already downloaded resources on the visitor's device. This is particularly important for mobile website use, as mobile devices often have slower internet connections. By caching resources, the browser does not have to download them each time from the server, which reduces loading times. This not only saves time, but also allows for more efficient use of available bandwidth, which is especially important with limited data volumes.

What are the Benefits of Browser Caching?

1. Faster Loading Times: When people visit a website, many files normally have to be downloaded. The browser cache stores temporary copies of these files. When the website is visited again, these files can be loaded from the cache, significantly reducing loading times.
    
2. Better Search Engine Ranking: Search engines favor websites that load quickly because it is an important factor for a positive user experience. Caching can improve website speed, which can have a positive impact on search engine ranking. Better visibility in search results leads to more visitors and potentially higher conversion rates.
    
3. Improved User Experience: Faster loading times not only mean that visitors spend less time waiting for the page to load, but they can also navigate the website more efficiently. This increases visitor satisfaction and reduces bounce rate.
    
4. Efficiency and Relief of the Server: Browser caching reduces the number of requests sent to the web server. As many resources are already stored in the visitor's cache, the server is less stressed. This contributes to relieving the server and saves bandwidth, which is particularly important for high traffic websites.
    

How Does Browser Caching Work?

Step 1: First visit to the website – Request resources

When visitors access a website for the first time, all necessary resources such as images, CSS and JavaScript files are requested from the web server and sent to the browser.

Step 2: Store resources in browser cache

With browser caching enabled, these resources are cached in the browser's cache.

Step 3: Next visit of the same website – Check cache

When you visit the same website again or navigate to another page of the same website, the browser first checks its cache. The browser checks if the resources stored in the cache are still up to date by checking their expiry dates.

Step 4: Load current resources from cache

If the resources stored in the cache are still current, they are loaded directly from the cache. Since the browser already has this data, page build-up is significantly accelerated.

Step 5: Request and update expired resources

If the resources in the cache have expired or changed, the browser requests them from the web server again and updates the cache.
 

3 Tips for Using Browser Caching

1. Adjustment of Expiration Times: Define appropriate expiry times for resources, based on how often they change. Static resources like images or CSS can be cached longer, while dynamic data needs shorter expiration times.
2. Use Cache Busting: Use cache-busting techniques to ensure that updates on your website are immediately visible to visitors. This prevents outdated resources from remaining in the visitor's cache.
    
3. Monitoring and regular testing: Monitor the performance of your website so you know that caching is working. Perform regular tests to ensure that caching settings are optimally set up.

What are the Differences Between Browser Caching and Server Caching?

Browser caching refers to caching resources on the client side to shorten loading times for repeat visits and reduce bandwidth usage. Server caching, however, aims to improve server performance by caching already generated data at the server level to speed up website delivery. There are various types of server caching, including object caching (for database queries), CDN caching (for content delivery via content delivery networks) and opcode caching (to optimize PHP performance). Both caching methods improve website performance, although they target different levels of data management on the web.

How to Use Browser Caching in WordPress?

There are two main methods to enable browser caching in WordPress: using plugins or editing server files directly.
 

1. Use of Plugins:

WordPress offers various plugins that can easily and efficiently enable browser caching. Some known caching plugins are:
 

- WP Rocket
- W3 Total Cache
- WP Super Cache
- WP Fastest Cache
- Hyper Cache
 

These plugins take over the caching process and greatly simplify it for website operators. WP Rocket, for example, stands out for its user-friendly interface and comprehensive caching features like cache warming or lazy loading.
If you are using caching plugins, you need to check if they are compatible with your hosting provider, as some hosting providers have caching restrictions. If your hosting environment supports caching plugins, you can configure and activate the caching settings directly in the plugin interface.
 

2. Direct editing of server files:

If you have access to your server files and feel up to the manual changes, you can activate browser caching by editing server files directly. This method involves adding headers to set caching rules. Be very careful when editing server files, as errors can affect your website's functionality. The manual process looks something like this:
 

3. Access to Server Files: Make sure you have access to your website's server files. This is usually done via an FTP program or your hosting provider's file management tool.
 

4. File Editing: Depending on which server your website is hosted on, you need to add certain pieces of code to the server files to enable browser caching. On an Apache server, you typically edit the. htaccess file, while on an Nginx server, you make changes in the server configuration file.
 

5. Adding Caching Rules: You need to add certain pieces of code to these files to set cache-control and expires headers for various file types. Cache-control determines how long the files should be cached, and expires indicates when cached files should be renewed.
 

6. Adjust Settings: Next, adjust the cache-control settings to define whether the files should be cached publicly or privately, depending on your requirements.
 

7. Save the Settings: Once you have made and saved the necessary changes to the files, your new caching settings will automatically be activated.
 

If you are unsure or have no experience editing server files, you should contact server support. This way you can be sure that the changes have been implemented correctly. Backups of your website are always a good precaution before making major changes.

What Is Cache Busting?

Cache Busting is a technique that ensures that the browser always loads the latest version of a file and not a previously cached version. When static files are cached in the browser cache, changes to a website may remain invisible to visitors because the browser retrieves the older version from the cache. Cache Busting solves this problem by forcing the browser to load the current version of the file from the server instead of the cached version. There are various methods for this, including renaming the files with the current version number.

What Tools Are Suitable for Browser Caching?

Seobility

Google Search Console

Screaming Frog SEO Spider

Sistrix

Ahrefs

Semrush

Yoast

You can find more tools in the SEO category on OMR Reviews.

Conclusion

Browser caching is a simple and effective method for optimizing website performance. It not only enables faster loading times, which improves user friendliness and satisfaction, but also relieves the servers, especially under high visitor load. In addition, browser caching plays an important role in search engine optimization, as loading speed is a key factor for ranking in search engines like Google.