Is your website slow? How to tell in two minutes (and what to do next)

"My site is fine" usually means "it opens fast for me on the office computer, on fibre, with a warm cache". Your customer opens it on a phone, in the street, for the first time. That's where a website is slow or it isn't. This article gives you three ways to measure it in two minutes, tells you what almost always slows a site down, and what we did to take a real website from 5.4 to 2.4 seconds.

What "slow" means, in numbers

Google measures speed with a metric called LCP (the time until the main block of the page is painted). Its thresholds are public:

• Up to 2.5 seconds: good.
• 2.5 to 4 seconds: needs improvement.
• Over 4 seconds: poor. And that's where a huge share of business websites live.

There's a second number almost nobody looks at: server response time (TTFB), how long your site takes to send the first byte. If it's 2 or 3 seconds, the page is blank for that long, whatever the design does.

Three ways to check it in two minutes

1. PageSpeed Insights (free, from Google). Paste your address and look at the "Mobile" tab. Note the LCP and the server response time. It's the same yardstick Google uses to rank you.
2. Your own phone, on mobile data. Turn off wifi, open a new tab and visit your site as if you'd never seen it. Count out loud. If you get to "four", you have a problem you can't see from the office.
3. Our free check. At app.wordnext.tech/comprobar you paste your address and within seconds we tell you what your site is built with, how much content it has, whether it can be migrated without rebuilding it, and how an AI would read it. It doesn't measure speed, but it tells you what's underneath — which is usually where the cause is.

A real, measured case: Olvidos

Before (WordPress): 5.4 seconds to load and 4.9 seconds of server response.

After (Next.js): 2.4 seconds to load and 0.2 seconds of response.

Same design, same content, same domain. The figures come from PageSpeed and you can see them live on our work page and in the home page demo, where your own browser times both versions.

What slows a website down, almost every time

After opening a lot of sites from the inside, the causes repeat:

• Plugins. Each one loads its script and stylesheet on every page, whether the page uses it or not. Thirty plugins are thirty tolls; we counted them in the autopsy of a WordPress with 38 plugins.
• Visual page builders. The drag-and-drop builder weighs more than the site itself, and the visitor downloads it on every visit.
• Shared hosting and PHP. The server has to assemble the page on every request. That's where the 2 or 3 seconds of response come from.
• Untreated images. A 4 MB photo on the home page wipes out any other optimisation.
• Cache plugins to paper over the above. They help sometimes and complicate things always; we explain it in why your WordPress is still slow with caching.

What to do next

If your LCP is over 4 seconds and the server response is over 1, compressing photos won't fix it: changing how the site is built will. A site built with Next.js reaches the browser as ready-made HTML, with no plugins to load, served from a network of servers close to the visitor. That's why the server answers in tenths of a second, not seconds. How to make that change without losing rankings is in the WordPress to Next.js migration guide.

No fluff: not every slow website needs rebuilding. If your LCP is around 3 seconds and the server responds in under half a second, optimising images and removing a couple of plugins may be enough. Measure first; decide after.

Start with the free check: in five seconds you'll know what your site is built with and whether it can be migrated. If you'd rather we measure it and tell you what's slowing it down, the audit is free and comes with numbers.