How to fix page speed warning on BigCommerce
Reduce your page load time to under 1.5 seconds by compressing images, eliminating render-blocking resources, and enabling caching so Google and shoppers experience a fast site.
Steps for BigCommerce
- Images: In Storefront → Image Sizes, confirm image dimensions match the largest display size in your theme. Upload images already resized and compressed; BigCommerce serves images through Akamai CDN automatically.
- Theme scripts: In Storefront → Themes → Advanced → Edit Theme Files (Stencil CLI or in-browser editor), open 'templates/layout/base.html'. Add 'defer' to non-critical <script> tags.
- Apps: In Apps → My Apps, remove all apps you are not actively using — each may inject storefront scripts.
- Script Manager: In Storefront → Script Manager, review every third-party script. Set loading to 'Footer' and method to 'Defer' wherever possible.
- CDN: BigCommerce includes Akamai CDN for static assets automatically. For additional optimisation, add Cloudflare in front of your domain via DNS settings at your domain registrar.
- Verify: Use Google PageSpeed Insights and BigCommerce's built-in Lighthouse reports (available under Storefront → Themes → ...) to track improvements.
What is page speed warning?
Page load time is how long it takes for your store's pages to fully appear in a visitor's browser. Search engines measure this as part of "page experience," and a load time above 1.5 seconds is considered slow. It's not just one thing — slow pages are usually caused by a combination of oversized images, too many scripts or stylesheets, no caching, and an underpowered hosting plan. Fixing page speed means identifying and removing those bottlenecks one by one.
Google uses Core Web Vitals (which include load speed signals like Largest Contentful Paint) as a direct ranking factor, meaning a slow store can rank lower than a faster competitor even with identical content. Every additional second of load time measurably reduces conversions — studies consistently show that a 1-second delay can cut conversion rates by 7–20%, directly costing you revenue. Slow pages also hurt mobile shoppers disproportionately, and since Google uses mobile-first indexing, poor mobile speed harms your desktop rankings too. Fixing speed is one of the highest-ROI improvements an ecommerce store can make.
See the complete Page speed warning guide for every platform and the full background.
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