How scalable is WordPress?

The WordPress website proudly boasts that “27% of the web uses WordPress, from hobby blogs to the biggest news sites online.” The 60 million plus websites that are powered by WordPress range from small blogs with only a handful of followers, to internationally-recognised news websites, attracting millions of page views a day. This demonstrates not only just how large and how dominant WordPress is, but also how scalable it is.

It’s estimated that more than 500 new sites are launched every day that use WordPress. Not every one of those will be for a large corporate. But many of those are for small and medium sized companies that have big plans, and which – as they become larger and more successful – will want to scale up their website at some point. And it’s precisely because WordPress is so scalable that it is chosen for so many websites in the first place.

Which large, well-known websites run on WordPress?

Some of the world’s biggest music celebrities, whose sites attract considerable volumes of traffic, use WordPress. These include: Beyoncé, Snoop Dogg, LL Cool J, Tom Jones, Justin Bieber, Kylie Minogue and The Rolling Stones. Even Twitter’s most-popular figure, Katy Perry, who has more than 95 million followers, has her site run on WordPress.

But it’s not just entertainers who require scalability. Business sites including Mercedes Benz, Bacardi, the LinkedIn blog, PEI Media, SAP’s information platform, the Microsoft News Center, The New Yorker magazine, Tilda Rice, The Rotary Club, Sony Music, Marks & Spencer For Business and Vogue are all powered by WordPress.org. Each of these WordPress sites is capable of successfully serving the high volumes of daily traffic that they receive.

What makes WordPress so scalable?

Out of the box, WordPress is a high performance platform with powerful media management and high levels of security. On top of that though, it can be configured and tailored to bring so much more.

WordPress is highly customisable from a design point of view. It can be used as a simple blogging website using a built-in theme, or can be scaled to deliver a sophisticated design with complex architecture for use by a global brand.

To a humble or basic corporate “brochure” website, you can add all sorts of functionality. WordPress is extendable with more than 45 thousands plugins, which give all manner of features. You can add a web store, media galleries and video, contact forms, mailing lists, forums, analytics, SEO, carousel sliders, events calendars, social sharing, newsletter signups, advertising and affiliate links. And that’s just the plugins in the WordPress plugin directory. There are thousands more on sites like codecanyon.net.

Considerations when scaling up WordPress

To scale up a WordPress installation so that it meets the requirements of an enterprise website with millions of monthly page views or thousands of concurrent users, there are some factors to be taken into consideration. Organisations with these sorts of needs have to make provisions outside of a basic installation.

1. Search

Although WordPress’s search feature is fairly rudimentary, it is perfectly suitable for most websites. However, for very large sites, with millions of posts, the built-in WordPress search can be slow and doesn’t give users the kind of experience they want.

In such cases, WordPress does still scale up, but it needs a little help. There are open-source scalable search solutions – like Elasticsearch and Solr – that work with WordPress to optimise search indexes. They can deliver near-instant search results across millions, even billions, of source documents.

2. Caching

For enhanced performance, caching is a vital strategy. Caching is the temporary storage of data that allows future requests for that same data to be delivered more rapidly. There are many caching plugins available for WordPress that help up to a certain point. But for the very large-scale sites, established caching tools such as reverse proxies can alleviate server load. A reverse proxy acts as an intermediary service that collects and serves cached data to users without interrogating the WordPress database. The reverse proxy simply serves a static cache of data, eliminating the querying of the database and also the need to execute code or process commands.

3. Content delivery

Websites with large volumes of media or files can take advantage of a content delivery network (CDN) or a scalable network file storage system. These act in the same way as a reverse proxy, storing and distributing files and media separately from the WordPress installation. They can massively speed up delivery, giving visitors much faster results when pages are requested.

4. Horizontal scalability

For websites with high traffic demands, another consideration is to build the website with a flexible server base. Thus, when demand is high, you can call on extra servers to cope with the traffic. With today’s cloud-based options, this horizontal scalability means you can always have sufficient architecture on-demand if needed. This load-balancing can optimise the resources being used so that capacity is maximised and response times are reduced. All of this means that no single server is ever overloaded and your site doesn’t suffer any downtime.

So, how scalable is WordPress?

With the right infrastructure, services and resources, WordPress is highly scalable. It can serve tens of thousands of logged-in users at a time and deliver hundreds of millions of monthly page views. It can process page requests immediately and can produce lightning-quick results to search queries. It is flexible, upgradeable and ultimately can power all manner of websites, right up to the largest and most visited.