HTTP Archive sample: CWV pass rate with and without a booking widget
| Group | Pass with widget | Pass without | Homepages with widget (CrUX) |
|---|---|---|---|
| WordPress | 40.6% | 49.1% | 717 |
| Shopify | 58.7% | 57.8% | 230 |
| Webflow | 46.2% | 49.8% | 52 |
| Other platforms | 47.9% | 39.6% | 1,095 |
| Top 100K | 50.0% | 42.9% | 100 |
| Rest of top 1M | 46.3% | 42.6% | 2,002 |
| All homepages | 46.4% | 42.6% | 2,102 |
Source: PageSpeed Matters, HTTP Archive and CrUX, Sept 2026. Groups are small, especially Webflow and Top 100K.
Summary
Booking and scheduling widgets turn a visit into a meeting, which makes them one of the most direct conversion tools a service business can add. We looked at which tools sites embed, and how sites with a widget compare on speed.
Calendly leads clearly. It appears on 23,990 of 40.3 million homepages crawled, against 7,396 for Acuity Scheduling and 4,323 for HubSpot Meetings. On speed, the answer depends on the platform: booking-widget sites pass Core Web Vitals more often overall, but less often on WordPress.
What we measured
Adoption counts cover 40.3 million homepages crawled between January and October 2026, based on each tool's embed scripts.
Speed figures come from the HTTP Archive crawl of the top 1M sites from September 2026, on mobile, joined to Chrome UX Report (CrUX) field data at the 75th percentile. We found 2,646 homepages with a detected booking or scheduling tool, 2,102 of them with CrUX data. The groups are small, so read the platform splits as a guide. This is a correlation: a widget does not by itself make a site faster or slower.
Calendly leads booking widget adoption
Across 40.3 million homepages, Calendly is embedded on 23,990, Acuity Scheduling on 7,396 and HubSpot Meetings on 4,323. That puts Calendly at roughly three times Acuity.
The top 1M crawl, which covers only the most visited sites and detects tools differently, shows the same leader: Calendly is detected on 1,542 homepages there, far ahead of any other scheduling tool. The two samples are built differently, so their counts should not be compared directly.
The speed picture depends on the platform
Top 1M homepages with a booking or scheduling widget pass Core Web Vitals 46.4% of the time (2,102 with CrUX), against 42.6% without, while carrying a median 1.34 MB of JavaScript against 0.90 MB.
That overall advantage comes from non-WordPress sites. On other platforms, sites with a booking widget pass 47.9% (1,095 with CrUX) against 39.6% without. On WordPress the gap reverses: sites with a widget pass 40.6% (717) against 49.1% without, with a median LCP of 2,439 ms against 2,153 ms. On Shopify, booking widgets make no real difference: 58.7% pass with one (230) against 57.8% without.
One possible explanation is the kind of site rather than the widget. On WordPress, booking tools may arrive through plugins that add weight of their own, while elsewhere they may sit on simpler service sites. Our data cannot separate the two.
What this means for your site
A booking widget is worth having if visitors book from it, but it does not need to load on every page or during the first paint.
- Put the full embed on a dedicated booking page, and link to it from the rest of the site.
- Where you want booking inline, load the widget when the visitor clicks a button or scrolls to it.
- On WordPress, check whether the booking plugin loads its scripts site-wide, and limit it to the pages that use it.
- Reserve space for the embed so it does not shift the layout when it appears.
Sources
- PageSpeed Matters analysis of 40.3M homepages crawled January to October 2026
- HTTP Archive crawl of the top 1M sites, September 2026, mobile
- Chrome UX Report (CrUX) documentation, Google: https://developer.chrome.com/docs/crux
Frequently asked questions
What is the most popular booking widget?
Calendly. Across 40.3 million homepages crawled since January 1, 2026, it is embedded on 23,990, against 7,396 for Acuity Scheduling and 4,323 for HubSpot Meetings.
Do booking widgets slow down a website?
It depends on the platform. On WordPress, sites with a booking widget pass Core Web Vitals 40.6% of the time against 49.1% without. On other platforms they pass 47.9% against 39.6%, and on Shopify there is no real difference.
A booking widget can stay front and center for visitors who want it while loading only when they reach for it. Need help with this? See our conversion rate optimization agency.