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The Chrome User Experience Report (CrUX) data for March 2026 is now live on Theme Vitals. In this post, I’ll cover:

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Change in data population

  • The total number of Shopify websites stayed nearly the same for both mobile and desktop devices (0.00% change).
  • New themes added this month: Seventh, Pebble, Rad, Unity, Cypress, Homage.
  • Themes dropped due to not enough data: Nexa.
  • I now show 348 (up from 343) total themes. 239 have performance data for mobile devices and 206 for desktop devices.

Shopify overall performance changes

Here are the median, min, and max performance numbers on mobile for all the Shopify themes measured on mobile devices:

image.png (For a more accessible version, see it live on the website: Aggregations).

Websites passing All Core Web Vitals increased by 1.10 percentage points to 86.40%. On desktop devices, it increased by 0.50 percentage points to 86.10%.

For Largest Contentful Paint (LCP), mobile improved by 0.60 points and desktop by 0.30 points. For CLS, mobile devices increased by 0.20 points while desktop decreased by 0.60 points. For INP, mobile decreased by 0.1 points and desktop stayed the same at 100%.

Number of themes with improved (and worsened) performance

This month, about 2/3 of the themes improved in performance on mobile and less than half on desktop.

image.png (For a more accessible version, see it live on the website: Aggregations).

Update on new flagship Shopify theme Horizon

Horizon improvements are tapering off still leaving it as a low-performing theme.

We now have a full month of data with the fix for the bug in Chrome that might explain a portion of the performance issues.

Desktop performance got slightly worse by 0.4 points to 90.2% of sites having good performance. Mobile improved slightly by 0.7 points to 72.7%. The improvement slowed down compared to last month which leads me to believe that the bug wasn't the biggest performance issue. Horizon still struggles quite a bit with loading speed and interaction speed on mobile. The native Shopify published data looks better due to Safari data being included. However, I would still be cautious about using these themes until they can improve some more, especially if your target market includes customers with Android phones.

As a reminder, here are the differences in our data populations:

  • Their data only shows the last 3 version releases, not all versions live on websites.
  • Our data includes only websites covered in the Chrome User Experience Report, about 600K, while theirs includes all sites using a custom domain (not using myshopify.com).
  • Similarly, our data only reports Chrome on Chromium. On mobile devices, this means mostly Android. The biggest difference is that their data includes iPhones which is a large chunk of US and Canadian shoppers.
  • Their data combines mobile and desktop so some of the nuance is lost in averaging.

As it stands, Horizon is ranked 219th out of 239 themes on mobile performance, which is where most ecommerce traffic lives now.

See full data on the Horizon theme page.

Most improved themes

For mobile devices, these themes had the most improvement in passing all Core Web Vitals:

  1. Boutique: 12.3 points (160 origins)
  2. Kidu: 10.8 points (57 origins)
  3. Volume: 7.7 points (81 origins)
  4. Igloo: 7.7 points (84 origins)
  5. Champion: 6.9 points (171 origins)

For desktop devices, these themes improved the most:

  1. Whisk: 7.2 points (124 origins)
  2. Masonry: 7.1 points (171 origins)
  3. Drop: 6.4 points (52 origins)
  4. Purity: 5.9 points (64 origins)
  5. Barcelona: 5.9 points (63 origins)

When themes on these lists have a small number of origins/market share, some of the improvements could be due to the underlying population of websites changing.

Highest market growth

As a reminder, the market share numbers calculated in Theme Vitals are not the same as number of installs. Here, we’re calculating market share based on the number of origins (websites/domains) in CrUX. CrUX only shares data for websites that reach a certain threshold of popularity. This threshold sometimes changes. To learn more, check out the methodology page for CrUX.

Growth in number of origins

The themes that already have the largest market shares usually have the highest growth in number of origins.

Mobile

  1. Horizon: 1610
  2. Tinker: 262
  3. Concept: 175
  4. Hyper: 161
  5. Atelier: 137

Desktop

  1. Horizon: 469
  2. Hyper: 124
  3. Concept: 93
  4. Ignite: 67
  5. Sleek: 62

Percent growth in origins

Raw growth is interesting but usually focuses too much on the existing themes with high market share. Here, I show which themes are growing the fastest on a percentage basis.

Mobile

  1. Krank: 34.7%
  2. Maximize: 30.3%
  3. Purity: 22.0%
  4. Allure: 16.7%
  5. Tinker: 16.6%

Desktop

  1. Purity: 28.0%
  2. Maximize: 25.6%
  3. Futurer: 22.2%
  4. Edge: 19.0%
  5. Ritual: 16.5%

Closing

Don't forget to check for the latest updates for the Fastest Shopify Themes.

The Theme Vitals site and this newsletter are meant to be a helpful resource to the Shopify community. Consider sponsoring or upgrading to a paid subscription to help develop new features.

As always, if you have ideas for new features or other improvements, let me know!

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