I need Help In Site Speed Improvement

[Umerniceg]

My site is on Shopify. My Brand Name is Leather Apron. Under search console core web vital I found zero issues regarding page speed.

My developer check complete site but not found issue regarding speed. but under page speed insights I found my site performance 51, accessiblity 89, and best practice 73. that is very poor. I need help how I can improve these matrics.

[ChrisChu5]

Quickly looking at the results for PSI, it seems like there’s a few things you could do to improve your scores there.

• Improve image load times, this can be achieved by either reducing the size of your assets, changing the image formats to something like .webp, or you could use an image CDN
• Total blocking time is pretty high. You can reduce this by removing or at least deferring unused JS scripts (apparently you have around 1330 KiB unused JS on your site)
• You have 135 KiB worth of unused CSS. If it’s unused throughout your store, you can remove them or at least split up CSS by templates so it only loads when the page requires it.
• You’ve got 4 preconnect links, make sure you pick 2-3 important ones.

There’s some more stuff you could do but doing these would move the needle on your PSI scores!

[AiRockers]

@Umerniceg,

There are a few things you can do.

Optimize image sizes. Check the images below.

There are a few render-blocking requests; check the screenshot below.

I found some requests and resources taking time to load. Have a look at them.

Optimizing them will improve the page load time of your store.

Thanks!

[Umerniceg]

thanks a lot such a valuable response. all these things already checked by my developer. He said nothing work out.

[mastroke]

We check the Store in the Pages speed Insight and getting below speed and we identify some key problem:

Low Performance Score (Mobile: 36 / Desktop: 64)
High LCP (Largest Contentful Paint)
Mobile: 17.5 (very high)

High TBT (Total Blocking Time)
Mobile: 860ms
Desktop: 870ms
What do these metrics mean?

1. LCP (Largest Contentful Paint)
   This measures how long it takes for the main visible content (like banner image or hero section) to load.
   Good: under 2.5 to 3.0 seconds
   Your case: its very high

Common causes:
Large banner images
Sliders/carousels
Slow server response
Heavy apps/scripts loading first

2. TBT (Total Blocking Time)
This measures how much time the browser is blocked by heavy JavaScript before the page becomes interactive.
Good: under 200ms to 250ms
Your case: very high, especially on desktop
Common causes:
Too many apps
Third-party scripts (trackers, chat, upsell apps)
Heavy theme JS
Recommended Fixes
Here are the most effective improvements you can make:

1. Optimize Images (Very Important)
   Compress banner/hero images
   Use next-gen formats (WebP)
   Avoid large sliders on homepage
2. Reduce Apps
   Remove unused apps
   Apps add JS which increases TBT
3. Delay Non-Critical Scripts
   Defer or delay apps like:
   Chat widgets
   Tracking scripts
   Review apps
4. Simplify Homepage
   Reduce sections, sliders, animations
   Focus on faster first load
5. Check Theme Performance
   Some themes are heavy by default
   Test with a default theme like Dawn for comparison

[AiRockers]

At this stage, basic optimizations like compressing images or removing a few apps may not be enough.

Current Mobile LCP which is more than 15s usually indicates that the browser is waiting too long before rendering the main visible section of the page. In many Shopify stores, the real issue comes from render-blocking JavaScript and how the theme loads sections/apps.

The store likely needs a deeper performance audit focused on:

1. Above-the-fold rendering

• The hero section should load first without waiting for sliders, animations, reviews, popups, or tracking scripts.

• If using a slider/carousel, replace it with a single static hero image on mobile.

2. Third-party app scripts

• Many apps continue loading scripts even after uninstalling.

• Check Theme.liquid and App Embeds for leftover scripts.

• Delay non-essential scripts using requestIdleCallback or deferred loading.

3. Theme architecture

• Some premium themes look good visually but are extremely heavy.

• Test the homepage on Dawn theme with the same content.

• If performance improves significantly, the issue is the theme structure itself.

4. JavaScript execution

• TBT around 860ms means the browser is blocked by heavy JS.

• Split large JS bundles and load features only when needed.

• Disable animations/parallax effects on mobile.

5. Homepage content overload

• Too many sections on the homepage dramatically increase LCP.

• Reduce:

  • sliders

  • video banners

  • animated sections

  • app widgets above the fold

6. App-by-app performance testing

• Duplicate the theme.

• Disable all app embeds.

• Re-enable one by one while testing Lighthouse scores.

• This usually identifies the actual bottleneck quickly.

7. Fonts and media

• Self-host fonts locally.

• Use only WOFF2 fonts.

• Preload the primary hero image and main font.

In many cases like this, the biggest improvement comes from:

• simplifying the homepage,

• removing heavy app scripts,

• and rebuilding the above-the-fold section for mobile-first loading.

A properly optimized Shopify store should usually achieve:

• LCP under 3s

• TBT under 200ms

• Mobile score 70–90+
  without sacrificing design too much.

Thanks!

[Wsp]

1. Performance (51)
   The main issues are LCP and TBT.

   • For LCP, convert images from JPG/PNG to WebP format and ensure each image size is below 100 KB.

   • To achieve faster page loading, implement Critical CSS by inlining the essential “above-the-fold” styles directly into the HTML. This reduces render-blocking resources and significantly improves the LCP score.

   • For TBT, remove any unused or unnecessary Shopify apps, as they increase JavaScript execution time and affect performance.

2. Accessibility

   • Add proper alt text to all images.

   • Fix contrast issues where both the background and text colors are too light, as this negatively impacts accessibility scores.

   • Add proper labels to buttons instead of using only icons, so screen readers can understand their purpose.

3. Best Practices

   • Ensure image dimensions are properly defined in the code to avoid layout shifts.

   • Check SSL and overall website security, and make sure there are no unsafe links or insecure scripts included on the site.