On real visits, Jimdo, Duda, GoDaddy and Wix have the best share of sites passing Core Web Vitals on mobile, while Squarespace and Weebly score lowest in Lighthouse’s lab test. Most “fastest website builder” articles we read don’t use field data. This one does.
We make Atelier201, which builds Astro sites, so we read this data closely, including the parts that surprised us.
Where the numbers come from
The HTTP Archive Core Web Vitals Technology Report combines the Chrome UX Report (what real Chrome users experienced) with detection of what each site is built on. We used its public API for September 2026, on mobile.
A site “passes” when its 75th percentile visit is rated good on all three metrics: LCP (how fast the main content appears), INP (how fast the page responds) and CLS (how much it jumps around).
It describes what the typical site on a platform gets, including badly made ones. It can’t tell you how fast a specific site will be.
Who passes most often
The closed builders do well because the company controls everything: hosting, images, scripts and defaults. Wix did a lot of work to get here. You can’t make a Wix site slow in most of the ways you can make a WordPress site slow.
The bottom of the table is about defaults. Lovable’s sites are mostly client-rendered React apps, which have a lot of work to do in the visitor’s browser before anything appears.
Who sends the least
Here the order changes a lot. Wix sends about five times the JavaScript of Jimdo and still does well in the field, which tells you that page weight and field pass rate are different things. A fast phone on a fast connection forgives a lot.
Weight still matters for three reasons: visitors on older phones, the people paying for mobile data, and AI crawlers, which generally read your HTML without running your scripts.
The full table
| Technology | Sites measured | Passes CWV | LCP good | INP good | CLS good | Median page | Median JS | Lighthouse performance | Lighthouse SEO |
|---|---|---|---|---|---|---|---|---|---|
| Jimdo | 21,093 | 93.8% | 96.7% | 98.7% | 97.3% | 1,737 KB | 336 KB | 62 | 85 |
| Duda | 42,026 | 85.8% | 94.0% | 94.6% | 93.3% | 1,888 KB | 744 KB | 54 | 92 |
| GoDaddy Website Builder | 4,510 | 82.0% | 91.9% | 93.5% | 89.1% | 2,222 KB | 897 KB | 60 | 92 |
| Wix | 177,709 | 80.9% | 84.8% | 92.6% | 97.9% | 2,768 KB | 1,757 KB | 61 | 96 |
| Shopify | 445,297 | 76.2% | 87.7% | 86.7% | 92.4% | 4,015 KB | 2,288 KB | 48 | 92 |
| Ghost | 2,932 | 72.8% | 86.5% | 94.4% | 85.0% | 2,426 KB | 1,102 KB | 65 | 96 |
| Webflow | 59,483 | 71.3% | 78.6% | 88.0% | 93.6% | 3,480 KB | 926 KB | 63 | 96 |
| Squarespace | 89,052 | 71.0% | 78.0% | 97.3% | 89.5% | 3,572 KB | 1,495 KB | 30 | 92 |
| Framer | 11,319 | 70.8% | 83.4% | 80.3% | 94.2% | 3,083 KB | 816 KB | 67 | 100 |
| Hostinger Website Builder | 4,952 | 51.3% | 53.6% | 91.0% | 95.9% | 1,852 KB | 564 KB | 64 | 96 |
| WordPress | 2,658,175 | 48.3% | 55.4% | 90.3% | 87.3% | 2,720 KB | 677 KB | 43 | 92 |
| Weebly | 17,820 | 41.1% | 44.8% | 69.6% | 49.5% | 3,072 KB | 1,840 KB | 32 | 92 |
| Lovable | 5,613 | 17.3% | 23.3% | 49.2% | 80.2% | 1,781 KB | 432 KB | 63 | 100 |
What about frameworks like Astro?
Astro, Next.js, Gatsby and Vite aren’t website builders. They’re frameworks that developers and AI code tools build with, so these numbers cover everything from personal projects to company sites. We list them apart, because we build on Astro and because AI tools pick the others so often.
| Framework | Sites measured | Passes CWV | LCP good | INP good | CLS good | Median page | Median JS | Lighthouse performance | Lighthouse SEO |
|---|---|---|---|---|---|---|---|---|---|
| Astro | 47,277 | 71.1% | 81.1% | 85.0% | 93.6% | 1,358 KB | 409 KB | 70 | 100 |
| Gatsby | 9,278 | 43.7% | 64.4% | 76.0% | 71.4% | 2,445 KB | 1,020 KB | 51 | 96 |
| Next.js | 395,345 | 35.7% | 53.5% | 59.7% | 73.5% | 2,170 KB | 822 KB | 53 | 96 |
| Vite | 107,259 | 9.2% | 39.3% | 13.9% | 33.6% | 2,791 KB | 1,497 KB | 38 | 91 |
“Astro is faster than Wix” is too simple. That’s the sentence we’d have liked to write. The median Astro site passes less often than the median Wix site in the field, at half the weight. Many Astro sites are personal projects on free hosting, with large images and third-party scripts, and the framework can’t fix those. What Astro gives you is a very low starting weight, and the rest depends on what you add.
What we’d take from this
Lighthouse and field data disagree a lot. Squarespace scores 30 at the median in Lighthouse’s throttled lab test and still passes for 71% of real visitors. Use the lab to find problems, and the field to judge results.
Lovable’s number is a snapshot. Its low score mostly reflects apps on its older client-rendered stack. New apps have been server-rendered since May 2026, so we’d expect this to change. Reread it in a year.
WordPress’s number is a warning about defaults. 2.6 million sites are in that median, and many are on cheap hosting with heavy themes. Its INP (90.3%) is fine; its LCP (55.4%) is the problem, and that usually means hosting and images.
The quiet tools lead. Jimdo and Duda rarely show up in comparison articles, and they lead on real visits, though both score far lower in Lighthouse. Read Jimdo and Duda against us.
Where Atelier201 stands
We ran Lighthouse’s mobile test three times on each of two real sites on our runtime. Both scored 100 for performance every time, with an LCP of 1.4 s and 1.8 s, 178 KB and 351 KB in total, and 8 KB and 7 KB of script. Those are lab numbers, so compare them with the Lighthouse and weight columns above. A site starts this light because it’s static HTML, served from Cloudflare’s network. See how that compares with each builder.
How to check your own site
- Open PageSpeed Insights and enter your address. The top section is field data, if you have enough traffic.
- Look at LCP first. Over 2.5 seconds usually means large images or slow hosting.
- In Chrome DevTools, open Network, reload and read the total. Compare it with the medians above.
- Fix images before you consider moving platforms. It’s the cheapest fix, on every platform.
