Shopify Theme Vitals: March 2025
Welcome to the monthly update! Consider sponsoring this newsletter to support new feature development for this project.
The Chrome User Experience Report (CrUX) data for March 2025 is now live on Theme Vitals. In this post, I’ll cover:
- ✨ New features ✨
- Change in the data population
- Aggregated theme performance changes
- Most improved themes for web performance
- Highest growth themes in market share
Thanks to Cronix
Thank you to our corporate sponsor, Cronix, a full-service ecommerce and digital agency.
You can add your individual support through a paid subscription or through Github or Ko-fi.
New features
I'm excited to share a number of new features this month! First off, I've made the Core Web Vitals aggregations component more readable than the old chart:
On that same page, I've added a chart that shows the number of Shopify origins/websites per month so you can quickly see if there were any significant changes in the data population:
Now to even bigger changes... I now include every theme with at least one data point in the latest month's data. I still only show actual performance data for themes with at least 50 websites, but you can at least see market rank, growth trends, number of websites, and more now.
As you may have spotted in the previous screenshot, the other big change is a new chart showing the distribution of theme versions for a theme. This should help you better understand the context behind your data. For example, maybe the latest version rolled out a performance improvement, but shops haven’t updated their theme yet so the performance numbers don't reflect it. Here's the data for Dawn, for example:
Change in data population
The total number of Shopify websites included in the data set decreased slightly.
Due to the massive change in which themes to include, the number of new themes increased a lot. No themes were dropped. I now show 283 total themes.
Aggregated performance across all themes
Here are the median, min, and max performance numbers on mobile for all the Shopify themes measured on mobile devices:
(For a more accessible version, see it live on the website: Aggregations).
On mobile devices, the median performance improved for good LCP by 1.2 points. All other numbers (desktop and mobile) changed less than 1 point.
Most improved themes
For mobile devices, these themes had the most improvement in passing all Core Web Vitals:
- Creative
- Maker
- Publisher
- Forge
- Vantage
For desktop devices, these themes improved the most:
- Avante
- Sydney
- Mr Parker
- Mobilia
- Starlite
Most of the themes on both those lists have a smaller number of origins/market share in the CrUX data set. Thus, some of the improvements may be due to better theme code, but with fewer data points it could also 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. Dawn returned to the top 5 this month:
Mobile
- Trade
- Concept
- Dawn
- Enterprise
- Impact
On desktop, the top 5 themes are:
Desktop
- Concept
- Trade
- Enterprise
- Sleek
- Impact
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
- Wonder (67% wow)
- Ascent (37%)
- Ignite (29%)
- Sleek (28%)
- Pinnacle (21%)
Desktop
- Ascent (51%)
- Wonder (49.2%)
- Ignite (49.1%)
- Sleek (35%)
- Pinnacle (23%)
Closing
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!