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The Chrome User Experience Report (CrUX) data for December 2025 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 increased by 0.02% to 602,654 on mobile devices. On desktop devices, it decreased by 0.07% to 288,690.
  • New themes added this month: Supreme, Victory, Stockist, Elemento, Cypress, Mosaic, Fullframe, Mix, Vino.
  • Themes dropped due to not enough data: none.
  • I now show 337 (up from 328) total themes. 232 have performance data for mobile devices and 195 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 stayed the same at 83.90% on mobile. On desktop devices, it decreased by 1.15 percentage points to 84.20%.

For Largest Contentful Paint (LCP), both mobile and desktop devices declined by 0.35 percentage points. For CLS, mobile devices improved by 0.05 points while desktop decreased by 0.4 points. For INP, mobile improved by 0.15 points and desktop got worse by 0.1 points, dropping out of 100% for the first time.

NEW: Number of themes with improved (and worsened) performance

This month, I'm happy to share a new feature I just rolled out - you can now see pie charts on the aggregations page which show the number or percent of themes which improved, worsened, or stayed the same for their passing all CWV metric:

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

Update on new flagship Shopify theme Horizon

Horizon is still struggling with performance. I don't think they are actively improving it at the moment so it might be a while before we see any movement. The poor performance is driven by LCP and INP which are arguably the 2 most important web vitals metrics. It struggles with all steps in loading speed - TTFB, FCP, and LCP. On mobile, it is ranked 217th out of 232 themes with data. It's doing a bit better on desktop at 60th out of 195.

This is unfortunate as Horizon continues to grow and take over marketshare from faster themes. 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. Piano: 13.6 points (52 origins)
  2. Neat: 7.6 points (65 origins)
  3. Hyper: 6.6 points (994 origins)
  4. Nordic: 6.5 points (108 origins)
  5. Sitar: 6.4 points (110 origins)

For desktop devices, these themes improved the most:

  1. Foodie: 7.2 points (90 origins)
  2. Barcelona: 5.2 points (57 origins)
  3. Monaco: 4.9 points (79 origins)
  4. Split: 4.3 points (270 origins)
  5. Pursuit: 3.7 points (419 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: 2239
  2. Dawn: 463
  3. Savor: 260
  4. Prestige: 255
  5. Atelier: 247

Desktop

  1. Horizon: 486
  2. Hyper: 68
  3. Rise: 28
  4. Fabric: 23
  5. Savor: 19

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. It's no surprise that Horizon is leading here.

Mobile

  1. Purity: 109.7%
  2. Allure: 40.0%
  3. Horizon: 35.2%
  4. Edge: 32.1%
  5. Ritual: 29.4%

Desktop

  1. Edge: 27.5%
  2. Horizon: 23.1%
  3. Paris: 17.8%
  4. Hyper: 10.8%
  5. Heritage: 10.5%

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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