Tune Image Delivery by Template Importance
Not all pages deserve the same image optimization strategy. Your homepage hero and PDP galleries drive conversions — they need the fastest, highest-quality delivery possible. Use Next-gen formats (WebP/AVIF), responsive srcset attributes, and aggressive preloading for above-the-fold images on high-value templates. For collection pages and blog posts, lazy loading and lower-priority delivery is acceptable. Prioritize your optimization effort where it impacts revenue: product detail pages and the homepage. A 1-second improvement in PDP load time can increase conversion rates by 5-7%.
Prioritize Trust-Building Content Above the First Conversion Decision
On a product detail page, the user makes their buy/no-buy decision within the first viewport. Everything above that decision point must build trust: clear product photography, price transparency, shipping information, return policy highlights, and social proof (reviews, ratings, badges). Do not bury trust signals below the fold or behind tabs. Test different arrangements of these trust elements — the optimal order varies by product category and price point. For premium products, lifestyle imagery and brand story elements can increase perceived value before the price is shown.
Measure Speed and Conversion Together
Never optimize speed and conversion separately. A merchandising change that adds a beautiful product video but increases page load by 2 seconds might decrease overall conversion. Conversely, stripping all visual richness for speed can hurt brand perception and reduce purchase confidence. After every merchandising or design change, measure both Core Web Vitals (LCP, CLS, INP) and conversion metrics (add-to-cart rate, checkout completion). Use real user monitoring, not just lab tests. The goal is the fastest possible experience that still tells a compelling product story.
Technical Performance Checklist
Run through these for every Shopify store: (1) Enable browser caching for static assets. (2) Minimize and defer non-critical JavaScript — especially third-party scripts for analytics, chat widgets, and retargeting. (3) Use system fonts or limit custom font files to 2-3 weights. (4) Reduce DOM size — Shopify themes with 3000+ DOM nodes are common and slow. (5) Eliminate layout shifts from loading images and dynamic content. (6) Preconnect to critical third-party origins. (7) Audit and remove unused apps — each Shopify app adds JavaScript and HTTP requests.