A slow site is rarely a hosting problem

When a site feels slow, the first move is usually to upgrade the hosting plan. Occasionally that helps a little. Usually it does not, because the cause of the slowness rarely has anything to do with how much processing power the server has.

Here are the three causes we find most often, in the order we find them.

Images far larger than they are displayed

This is the most common cause and the easiest to fix.

A photo straight from a phone camera is several megabytes. The space it occupies on screen might be eight hundred pixels wide. The browser still downloads the entire original file and only then scales it down for display.

On a mobile connection a single image like that can take longer to arrive than every other part of the page combined. Ten of them on one page is not unusual, and it turns a two second load into a fifteen second one.

How to check it yourself. Open the page, press F12, go to the Network tab and reload. Sort by size. Anything over about 300 kilobytes is worth resizing.

Plugins that load everywhere

Every plugin adds its own JavaScript and CSS files, and by default those files load on every page, whether or not the feature is used there.

A site running twenty plugins routinely loads several times more code than it ever executes. A contact form plugin loads its scripts on your blog posts. A slider plugin loads on pages with no slider.

Auditing which plugins are still genuinely in use usually pays off far better than adding server capacity, and it costs nothing but an afternoon.

No caching

Without caching, the same page is assembled from scratch every single time anybody opens it. The server queries the database, builds the HTML, and sends it, then does the identical work again for the next visitor one second later.

For pages whose content changes rarely, which is most pages on most company sites, that work is entirely wasted.

Turning caching on frequently gives a larger improvement than two hosting tier upgrades combined, and on most platforms it is a setting rather than a project.

Measure before you spend

Upgrading hosting without knowing the cause is the same as raising an ad budget to compensate for a landing page that does not convert. You are paying more to work around a problem instead of paying less to remove it.

Run the page through any free performance tool first. It will tell you which of the three above is responsible, usually within a few seconds, and then you can spend money on the thing that is actually wrong.