Optimization

Performance & SEO

Sellzar is engineered for speed. Learn how we achieve top-tier Core Web Vitals and how you can maintain these scores.

Built-in Optimizations

Responsive Images

We use the srcsetattribute to serve the smallest possible image size based on the user's device resolution.

Critical CSS

Only the styles needed for the current page are loaded, minimizing render-blocking resources.

Lazy Loading

Images and heavy scripts are only loaded as they enter the viewport, significantly improving the Largest Contentful Paint (LCP).

JSON-LD Schema

Rich results for products, breadcrumbs, and articles are baked directly into the theme for maximum search visibility.

Search & Discovery

Sellzar uses Shopify's Predictive Search APIto provide instant results. You can customize the discovery experience in **Theme Settings > Search**.

Predictive Results
Toggle product, collection, and article suggestions in real-time.
Metadata Visibility
Optionally show or hide prices and vendors in the search dropdown.

Advanced Script Management

Sellzar uses a proprietary Conditional Asset Loader to ensure that heavy JavaScript libraries never block the initial render.

Model Viewer (.js)

The 900KB model-viewer.min.js library is only injected into the DOM if the theme detects a 3D model (media_type: 'model') on the current product page.

Dynamic Lucide Icons

Sellzar uses a custom SVG-injection system that only renders the icons currently visible on the screen, reducing DOM complexity.

Maintenance Tips

Avoid Too Many Apps
Every third-party app adds JavaScript that can slow down your store. Use Sellzar's native features instead of installing apps for wishlists, countdowns, or search.
Compress Your Images
Before uploading, use tools like TinyPNG or Shopify's integrated image compression to keep file sizes low.
Lighthouse Ready
Sellzar consistently scores **95+** on Google Lighthouse for Desktop and **85+** for Mobile, placing your store in the top tier of Shopify sites.