Great design and great performance can coexist on Shopify. The reward is real. The Deloitte and Google study Milliseconds Make Millions found that a 0.1 second speed improvement lifted retail conversions by 8.4 percent and increased average order value by 9.2 percent, which is a compelling reason to treat speed as a growth lever, not just a technical metric.
What “good” looks like for Core Web Vitals on Shopify
Google’s current guidance is clear. According to Web Vitals documentation from web.dev, a good Largest Contentful Paint should occur within 2.5 seconds, Interaction to Next Paint should be 200 milliseconds or less, and Cumulative Layout Shift should be 0.1 or less at the 75th percentile of pageviews across mobile and desktop. Google also confirmed that INP officially replaced FID in March 2024, which means responsiveness is now measured across all interactions rather than just the first.
If you run Shopify, your theme and content choices are the biggest levers. Shopify’s help center explains that theme code, apps, and third party tags are the primary contributors to slowdowns, and it recommends using performance optimized Online Store 2.0 themes, auditing apps, and limiting excessive sections per template.
Eliminate app bloat without losing capability
App installs are the fastest way to add features and the fastest way to tank LCP and INP if left unchecked. Shopify warns that uninstalling an app does not always remove its injected theme code, so you may need to manually remove leftover scripts or contact the developer. Start with a simple quarterly routine:
Inventory scripts and app assets on key templates with the Coverage panel and Network waterfall in Chrome DevTools, then sort by total transfer size and blocking time.
Remove nonessential apps, and replace heavy widgets with built in theme features where possible. If you must keep an app, load it on interaction or only on templates that need it.
Move third party tags into a tag manager, then follow the tag hygiene practices recommended in Google’s tag best practices guide to pause or delete low value tags.
After removals, recheck your field data in Shopify’s Web Performance reports, which Shopify notes are based on real user Core Web Vitals.
The 2024 Web Almanac shows why this matters. It reports that 92 percent of pages use third party resources and that scripts account for 30.5 percent of those requests. Cutting unnecessary third party JavaScript is usually the fastest way to reduce Total Blocking Time and improve INP.
Win LCP by targeting media first
On Shopify, the LCP element is often a hero image or product media. The HTTP Archive’s 2024 Page Weight chapter shows that images are the largest resource type on homepages, with a median of about 1,054 KB on desktop and 900 KB on mobile. That makes image discipline your first, best WPO bet.
Use Shopify’s CDN correctly. Shopify documents that stores run on a global CDN and that images are automatically optimized and can be served as modern formats. Lean into this by using Liquid’s image_tag filter to output responsive srcset and sizes rather than hard coding image URLs and dimensions.
Serve the smallest right sized asset. Shopify’s theme best practices recommend responsive images and explicitly warn against browser side downscaling. Set width and height to reserve space and prevent CLS.
Do not lazy load above the fold. Shopify’s guidance is to lazy load only below the fold and to keep the hero image and critical banner media eager.
Preload the hero. Shopify supports resource hints through the preload_tag and preload options on stylesheet_tag and image_tag. Preloading the LCP image often shaves hundreds of milliseconds off LCP.
Replace heavy embeds with facades. The Web Almanac describes import on interaction facades for video and social embeds. Show a poster image and load the full player only after click.
Control scripts and the render path
JavaScript is usually the second biggest weight class. The Web Almanac shows median homepage JavaScript near 613 KB on desktop and 558 KB on mobile, and it highlights the extra CPU cost of parsing and execution that hurts INP. Shopify’s official theme performance guide advises reducing JavaScript usage, avoiding frameworks when possible, and keeping minified bundles extremely lean, targeting 16 KB or less. Practical actions:
Defer or async noncritical scripts. Shopify explicitly calls parser blocking scripts a cause of delayed rendering and recommends defer or async on script tags.
Load features only when used. Shopify endorses import on interaction patterns for components like chat, carousels, and reviews. That removes wasted execution on pages where users never interact.
Host assets on Shopify. Shopify recommends hosting under the theme’s assets folder to keep critical connections on the same HTTP/2 origin and let the platform prioritize delivery.
Audit Liquid render time. Use Shopify Theme Inspector for Chrome to find slow loops and filters, then restructure logic outside hot loops. Faster server side rendering improves Time to First Byte and LCP.
Theme and content choices that keep you fast
Shopify is already doing a lot under the hood. The platform uses Cloudflare CDN, gzip compression, one year browser caching where possible, and automatic minification for requested CSS and JS. Your job is to avoid undoing this foundation.
Choose a performance minded theme. Shopify’s developer docs state that themes must average a Lighthouse performance score of at least 60 on home, product, and collection templates to be accepted into the Theme Store. If your existing theme lags, test a current Online Store 2.0 option such as Dawn to benchmark the gap.
Limit section sprawl and paginate large collections. Shopify’s help guidance warns that too many sections and long product grids degrade performance and recommends pagination for large collections.
Use a system font stack where brand allows. Shopify suggests system fonts to avoid render blocking font downloads. If you do use web fonts, preload the critical weight and subset the character set.
Measure in the field. Google explains that Core Web Vitals pass at the 75th percentile for all three metrics. Use Shopify’s Web Performance dashboard for RUM data, and PageSpeed Insights for template specific diagnostics.
How BoomSprint ships sub 2.5 second LCP without sacrificing design
At BoomSprint, we pair high end, animation led design with performance budgets and modular build systems, so brand polish never comes at the cost of speed. Our 5 step model compresses risk and time to value. Discovery builds a speed budget and a measurement plan. Prototyping validates interactions and motion before a line of code. Design systems and CMS modules let marketers edit content without developer handoffs. Our custom Shopify development emphasizes responsive media, lean scripts, and import on interaction for low impact apps. SEO is integrated throughout, not bolted on, which aligns structure, content, and performance from day one.
Explore recent work and see our approach in action on our portfolio, learn more about our services, and check transparent pricing. If you are starting fresh or replatforming, consider building on Shopify to take advantage of its global CDN, image pipeline, and performance tooling.
For ecommerce teams that want a site that loads fast, ranks, and looks premium, we can help you create a modular, speed minded Shopify storefront that your team can edit confidently. Get in touch with us through our contact page, and browse our practical strategy and SEO posts on the blog, including how to produce content that ranks in our guide on writing content that ranks on Google.
