How we cut a WordPress site's weight by 68% without losing its look

The site we inherited weighed in at roughly 4.2 MB on the homepage. Visitors were bouncing before it finished loading — especially on slow mobile networks. The client had two options: a full rebuild, or careful optimization without breaking the existing site. We picked the second.

In this case study, we share what we did in detail — numbers before and after each step, the tools we used, and the mistakes we made along the way.

Before we started

The site is a local food brand built on WordPress since 2021. Years of accumulation produced a mix of:

1. 14 plugins, 6 of which were truly unnecessary
2. Two web fonts at four weights each
3. Unoptimized images, some up to 800 KB
4. JavaScript libraries not used on the homepage

Step 1: Audit and measurement methodology

We started with careful measurement. Lighthouse in Mobile mode, WebPageTest from three regions, and Chrome DevTools Coverage.

Numbers you don't measure before the change can't be sold as improvements after. And you can't sell them to the client.

Step 2: Plugin cleanup

We reviewed each plugin carefully. Result: out of 14 plugins, we kept 7. Three of those we replaced with lightweight custom code.

Step 3: Images

Images were the biggest size offender. We added automatic WebP conversion, with AVIF as the first fallback, and used srcset at multiple sizes.

Step 4: Fonts

We trimmed fonts to two weights per family and subsetted Arabic glyphs to only what's used on the site. Size dropped from 720 KB to 180 KB.

Final result

After 12 working days and 200+ tests in staging, page size went from 4.2 MB to 1.35 MB. LCP from 3.8s to 1.1s.

Not every slow site needs a rebuild. Careful optimization is often much cheaper, lower-risk, and delivers results close to a rebuild.