If you are asking why is my website slow, you have probably noticed it yourself, or a customer has mentioned it. Either way, the useful move is to measure before you spend anything. A slow site is usually slow for a short list of boring reasons, and most of them cost very little to fix.
Below: what slowness costs you, the usual causes in the order worth checking them, a 15 minute test, and how to choose between fixing and rebuilding. It is written for small business owners, not engineers.
- Test first. Run your homepage through Google's free PageSpeed Insights on the mobile tab. Google's "good" mark for the main content to appear is 2.5 seconds or less.
- Fix the cheap things first: oversized photos, unused plugins and third-party scripts. That alone sorts out most small business sites.
- Then look at hosting. A cheap shared plan can cap how fast any site feels, however well it is built.
- The one thing that usually decides fix versus rebuild: whether the weight is in your content or in the platform underneath it.
Why is my website slow? Measure it first
"Slow" is a feeling until you put a number on it. Your own laptop, on office wi-fi, with the site cached, is the worst place to judge it. Your customers are on a phone, on 4G, opening the page cold.
Google publishes three targets it calls Core Web Vitals, measured at the 75th percentile of real page loads. Per Google's web.dev guidance, the main content should appear within 2.5 seconds (Largest Contentful Paint), the page should respond to a tap within 200 milliseconds (Interaction to Next Paint), and the layout should not jump around, with a shift score of 0.1 or less (web.dev, Google, 2025). Those three numbers are the yardstick for the rest of this article. For what each one means in practice, see how fast a website should load.
What a slow website costs you
Most of this research is older and overseas, so read the figures as direction, not a forecast for your site.
- Google's 2016 analysis of more than 10,000 mobile sites found 53% of mobile visits were abandoned when a page took longer than three seconds to load (Google via the AMP Project, 2016).
- Google and SOASTA research from 2017, reproduced in Deloitte's report, found the chance of a visitor bouncing rises 32% as load time goes from one second to three (Deloitte, Milliseconds Make Millions).
- A study commissioned by Google and run by 55 and Deloitte, covering 37 European and American brands, found that a 0.1 second improvement in mobile speed lifted conversion rates by 8.4% for retail sites and 10.1% for travel sites (web.dev, 2020).
People leave slow pages before they read them, and Google's ranking systems use these speed measures too. We cover the wider symptoms in our piece on signs your website is costing you customers, and the checkout side in why shoppers abandon carts.
The usual causes, most likely first
Check these in order. The early ones are cheap, and each one can account for most of a slow load on its own.
1. Photos that are far bigger than they need to be
A photo straight off a phone can be several megabytes, and it downloads in full even in a 600 pixel slot. Resize to the displayed size, save as WebP or compressed JPEG, and lazy-load images below the fold. The hero image usually sets your 2.5 second score, so start there.
2. Too many plugins, apps and scripts
Every WordPress plugin, Shopify app, chat widget, tracking pixel and review badge adds code the visitor's phone has to download and run. Make a list of everything on the site and ask what each one earns. If nobody can say, remove it and see what breaks.
3. A heavy theme or page builder
Multipurpose themes ship code for dozens of layouts you never use. You cannot always trim one without rebuilding the pages on it.
4. Hosting that is cheap and far away
Budget shared hosting puts your site on a crowded server, sometimes on the other side of the world. If most of your customers are in Sydney, ask where the server is and whether a content delivery network with a Sydney location sits in front of it.
5. Fonts, video and layout shift
Extra font files, autoplaying background video and images without set dimensions all hurt. Give every image a width and height so the page does not jump as it loads.
A 15 minute speed check you can do yourself
- Open PageSpeed Insights and test your homepage, then your busiest service or product page. Use the mobile tab, not desktop.
- Write down the LCP, INP and CLS numbers and compare them with 2.5 seconds, 200 milliseconds and 0.1.
- Scroll to the diagnostics and note the biggest files and the "unused JavaScript" warning.
- Open the site on your own phone with wi-fi off. Time how long until you can read the headline and tap a button.
- List every plugin, app and script. Mark the ones you cannot justify.
- Find out who hosts the site, which plan you are on, and where the server is.
- Retest after each change, one at a time, so you know which fix did the work.
Scores move between runs, so judge the pattern, not one number. A perfect 100 is the wrong goal. Passing the three thresholds on your real pages is the goal.
Fix it or rebuild it?
Fix it if the problems are in your content: big photos, spare plugins, old scripts. That is an afternoon of work, or a small job for a designer. Rebuild when the weight comes from the platform itself, such as a theme you cannot trim, a page builder wrapped around every page, or a site that has been patched for years and nobody dares touch it.
Our view: if the fixes above get you under the three thresholds, stop there and spend the money elsewhere. If they do not, a rebuild on a lean foundation is cheaper than paying to keep patching. We tune Core Web Vitals on every site we build as part of our SEO foundations, and the Fairfield law firm site in our Hussaini Law Group case study was built with fast mobile pages as a stated goal. If you are leaning towards a rebuild, see how our website redesign service works, and our website cost guide for what to budget.
What to ask your designer or host
- What are my LCP, INP and CLS scores on mobile today, and what will they be after your work?
- Which plugins, apps and scripts are you removing, and why are the others staying?
- Where is my site hosted, and is a CDN in front of it?
- How will you prove the result, and will you send before and after tests?
A good answer comes with numbers. "A faster site" is not an answer.
