Check your store speed.
Fix what's slowing it down.
Run a full Lighthouse audit on any Shopify store. Get Core Web Vitals, a performance score, and clear next steps.
What Does This Tool Measure?
The Shopify Speed Test runs a full Google Lighthouse audit on any URL using the PageSpeed Insights API. It tests your site on a simulated mobile device and returns a performance score from 0 to 100, along with Core Web Vitals - the metrics Google actually uses to evaluate your site's user experience.
- LCP (Largest Contentful Paint) - How long it takes for the main content to appear. Under 2.5 seconds is good.
- CLS (Cumulative Layout Shift) - How much the page jumps around while loading. Under 0.1 is good.
- TBT (Total Blocking Time) - How long scripts block the page from responding to clicks. Under 200ms is good. This is a lab proxy for INP (Interaction to Next Paint).
- TTFB (Time to First Byte) - How fast your server responds to the first request. Under 800ms is good.
Why Store Speed Matters
Store speed directly affects your bottom line. Research consistently shows that slower sites have higher bounce rates and lower conversion rates. A one-second delay in page load can reduce conversions by 7%. Google also uses page speed as a ranking factor, meaning slow stores get less organic traffic.
For Shopify stores specifically, speed problems tend to compound. Each app you install adds scripts and stylesheets. Over time, a store with 15-20 apps can become noticeably slower than a fresh install, even if each individual app seems lightweight.
Common Reasons Shopify Stores Are Slow
- Too many apps - Each app injects JavaScript and CSS into your storefront. Even apps you are not actively using may still load their code on every page.
- Uncompressed or oversized images - Large hero images and product photos that have not been optimized are one of the most common speed killers.
- Heavy themes - Some Shopify themes include excessive features, animations, and scripts that slow down every page load.
- Homepage videos - Auto-playing background videos look impressive but massively increase page weight and load time.
- Third-party scripts - Analytics, chat widgets, pop-ups, and marketing pixels all add up. Each external script is another network request and more JavaScript to process.
Quick Wins to Speed Up Your Store
- Audit your apps - Go to Settings > Apps in your Shopify admin. Uninstall anything you are not using. Some apps leave residual code - check with the developer if needed.
- Optimize images - Compress images before uploading. Use JPEG for photos and PNG only when you need transparency. Make sure your theme serves WebP when supported.
- Minimize homepage sections - Every slider, carousel, or product grid adds weight. Keep your homepage focused and limit it to essential sections.
- Defer non-critical scripts - If your theme supports it, set third-party scripts to load after the main content. This improves perceived load time.
- Use system fonts or limit custom fonts - Custom fonts require additional downloads. If you must use them, make sure font-display: swap is set so text is visible immediately.
Related Tools and Reviews
Use our other tools and reviews to optimize your Shopify store further:
- Shopify App Detector - See what apps any store is running
- Best Analytics Apps - Track performance metrics
- PageFly Review - Build faster landing pages