Why Your Agency-Built Website Scores 70 on PageSpeed

The Score You Probably Have

Open PageSpeed Insights, enter your website URL, and wait 30 seconds. If your site was built by a marketing agency in the last 5 years, the mobile Performance score is probably between 55 and 80. Orange territory.

That is not because your agency is bad at their job. It is because the tools they use (WordPress, Webflow, Squarespace) add overhead that tanks performance. Frameworks, plugins, tracking scripts, font loaders, and CMS infrastructure all compete for bandwidth on every page load.

A site that scores 70 on mobile loads in 3 to 5 seconds over a cellular connection. A site that scores 95+ loads in under 1 second. Google uses Core Web Vitals as a ranking factor. Your competitors with faster sites get a ranking boost you do not.

WordPress: The Plugin Tax

WordPress powers 43% of the web. It is flexible, extensible, and slow. A typical agency-built WordPress site has 12 to 25 plugins: SEO plugin, form plugin, caching plugin, security plugin, slider plugin, analytics plugin, and a page builder like Elementor or Divi.

Each plugin adds JavaScript and CSS to every page load. The caching plugin tries to compensate, but it is fighting the architecture. WordPress serves pages by querying a MySQL database, executing PHP, assembling HTML from template fragments, and then delivering it to the browser. That process takes 200 to 800 milliseconds before the browser even starts rendering.

A static HTML site skips all of that. The browser requests a file, the CDN delivers it, and rendering begins immediately. No database. No PHP. No plugin overhead. The entire page loads in 100 to 300 milliseconds.

Webflow: The Framework Overhead

Webflow produces cleaner output than WordPress, but it still ships a JavaScript framework to every page. The Webflow runtime handles interactions, animations, and CMS bindings. That JavaScript adds 50 to 150KB of overhead to every page load.

A Webflow site typically scores 75 to 85 on mobile PageSpeed. Better than WordPress, but still in the orange range. The Speed Index is usually 2 to 4 seconds. For reference, our static sites score 90 to 98 with a 0.9s Speed Index.

Webflow also hosts your site on their infrastructure. You pay $14 to $39 per month for hosting. A static site hosted on GitHub Pages or Cloudflare Pages costs $0. Over 3 years, that is $500 to $1,400 in hosting fees for a slower site.

Squarespace: The Template Ceiling

Squarespace is the easiest to launch and the hardest to optimize. The platform controls the entire rendering pipeline. You cannot modify the HTML output, cannot control script loading order, and cannot remove Squarespace's own tracking and analytics scripts.

Most Squarespace sites score 40 to 65 on mobile PageSpeed. The platform loads its full JavaScript framework, font subsystem, and analytics on every page regardless of whether you use those features. A simple 5-page brochure site carries the same overhead as a 100-page e-commerce store.

If your Squarespace site scores 50 on mobile, migrating to static HTML can bring that to 90+ without changing the visual design. Same look, 5x faster.

What a Low Score Costs You

Google confirmed Core Web Vitals (Largest Contentful Paint, First Input Delay, Cumulative Layout Shift) as ranking factors. A slow site does not get penalized outright, but a fast site gets a ranking boost. In competitive search categories, that boost is the difference between page 1 and page 2.

Conversion rates drop with load time. Research from Google shows that 53% of mobile visits are abandoned if a page takes longer than 3 seconds to load. Every second of load time after that costs roughly 7% in conversions.

For a site generating $50,000/year in leads, a 1-second improvement in load time could mean $3,500 in additional annual revenue. For a site generating $500,000/year, it is $35,000. The math compounds with traffic.

The Images Problem

Images are the single largest contributor to slow page loads. Agency designers upload high-resolution images without optimizing them. A 3MB hero image on a WordPress site adds 2 to 4 seconds of load time on a mobile connection.

Proper image optimization means: serving WebP or AVIF format, sizing images to the container (not uploading a 4000px image for a 400px container), lazy-loading below-the-fold images, and using responsive srcset attributes to serve different sizes to different devices.

Most agencies skip all of this. They upload the image from the photographer directly into the CMS. WordPress plugins like ShortPixel or Imagify try to fix it after the fact, but they add another plugin to the stack and often miss the srcset optimization.

Render-Blocking Resources

Open your browser's DevTools, go to the Performance tab, and look at the waterfall chart. The long blue and yellow bars at the top are render-blocking CSS and JavaScript files. The browser cannot show any content until those files finish loading.

A typical WordPress site loads 5 to 15 CSS files and 8 to 20 JavaScript files before the first pixel appears on screen. Many of those files are from plugins you installed for a single feature on a single page, but the scripts load globally.

A static site loads one CSS file and one JavaScript file. Both are minified. The CSS is under 30KB. The JavaScript handles mobile navigation and form validation. Total blocking time: 30 to 50 milliseconds. A WordPress site's Total Blocking Time is typically 200 to 500 milliseconds.

What to Do About It

You have three options, ranked by effectiveness:

Option 1: Optimize what you have. Compress images, defer JavaScript, enable caching, reduce plugins. This gets a WordPress site from 55 to 70. Maybe 75 if you are aggressive. You are still fighting the platform architecture.

Option 2: Migrate to static. Rebuild the site as static HTML/CSS. Same design, 90+ PageSpeed score. No CMS maintenance, no plugin updates, $0 hosting. This is what we do. Migration from WordPress starts at $2,500. From Webflow: $3,000.

Option 3: Start fresh. If you need a redesign anyway, build it static from the start. Standard sites run $3,000 to $6,000. You get a 90+ PageSpeed score, full schema markup, and you own every file.

Start with a free audit to see where your site stands. Or read about our migration service and pricing.