Why is my website slow? on BigCommerce

Load bottlenecks are reducing UX quality and ranking potential.

• Large media and scripts delay LCP
• Render-blocking resources slow first paint significantly
• Server response time is too high

Slow website speed harms user experience, conversion rates, and SEO. Google uses Core Web Vitals and related signals in ranking, and users abandon slow pages. Speed issues often come from large images, too many or blocking scripts, unoptimised hosting, or heavy page construction. Identifying the main bottlenecks—server, assets, or front-end logic—lets you target fixes that have the biggest impact. Practical context: prioritise one representative URL, confirm the exact blocker with Search Console and live testing, then apply the fix in templates or settings so the issue does not repeat site-wide. Track impressions, indexed page counts, and click recovery for at least two crawl cycles before closing the task. Practical context: prioritise one representative URL, confirm the exact blocker with Search…

Unoptimised or oversized images (wrong format, no compression, or no responsive images) are a frequent cause. Render-blocking JavaScript or CSS delays first contentful paint. Slow or overloaded hosting or CDN can increase server response time. Too many third-party scripts (analytics, ads, chat) add weight and delay. Database or server-side rendering can be slow on complex or poorly coded pages. Missing caching or compression on the server increases load for every request.

Common examples

A real-world example: after a site update, a business saw visibility drop for "Website slow". They checked Search Console, found the blocking issue, fixed it, and regained impressions over the following crawl cycles.

How to diagnose

Use Google PageSpeed Insights or Lighthouse to get Core Web Vitals and suggestions. Check Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS). Review the Opportunities and Diagnostics sections. Use Search Console's Core Web Vitals report to see field data. Test with real devices and throttled networks. Inspect network and main-thread activity in Chrome DevTools to find heavy or blocking resources.

Recommended fixes

Optimise images: compress, use WebP/AVIF where supported, and serve appropriately sized images. Defer or async non-critical JavaScript and minimise render-blocking CSS. Use a fast host or CDN and enable caching and compression. Reduce third-party scripts or load them asynchronously. Improve server response time (TTFB) with better hosting, caching, or code. Fix layout shifts by sizing images and ads and avoiding injected content above the fold. Practical context: prioritise one representative URL, confirm the exact blocker with Search Console and live testing, then apply the fix in templates or settings so the issue does not repeat site-wide. Track impressions, indexed page counts, and click recovery for at least two crawl cycles before closing the task. Practical context: prioritise one representative URL, confirm the exact blocker with Search Console and live testing, then apply the fix in templates or settings so the issue does not repeat site-wide. Track impressions, indexed page counts, and click recovery for at least two crawl cycles before closing the task. Practical context: prioritise one representative URL, confirm the exact blocker with Search Console and live testing, then apply the fix in templates or settings so the issue does not repeat site-wide. Track impressions, indexed page counts, and click recovery for at least two crawl cycles before closing the task. Practical context: prioritise one representative URL, confirm the exact blocker with Search Console and live testing, then apply the fix in templates or settings so the issue does not repeat site-wide. Track impressions, indexed page counts, and click recovery for at least two crawl cycles before closing the task.