It's the first question business owners ask when they see a 3D website: "Won't that be slow for my customers?" It's a fair worry. Most people find a local business on a phone, often on mobile data, and a site that stutters or takes ages to appear loses them.
The honest answer: 3D websites are slow when they're built carelessly, not because they're 3D. Here are the techniques we use on the free websites we build for local businesses, with real numbers from the live sites.
The principle: do the heavy work before the visitor arrives, send each device only what it needs, and give anyone on a weaker phone or a data plan a beautiful still version instead.
Here is everything each site publishes: every page, image, font and script. A visitor's phone downloads less than this, because it skips the version made for the other screen size.
| Site | Kind of 3D | Everything published |
|---|---|---|
| Amintiri | Scroll film of a cake with flowing sauce | About 1.5 MB |
| Casa Fresco | Live sea and sky, drawn in real time | About 1.8 MB |
| The Dome Cafe | 80-frame film, in desktop and phone versions | About 11.7 MB in total; the phone film alone is about 4.5 MB |
For comparison, a single photo straight off a modern phone camera is often several megabytes on its own.
The most realistic scenes (glass, sauce, steam, sunlight) are path-traced on our computers ahead of time and saved as a sequence of frames. The visitor's phone only has to show pictures in order as they scroll, which any phone can do. No graphics-heavy calculation happens on their device.
We render two versions of each film: a wide one for desktops and a tall one for phones. The site picks one, so a phone never downloads the desktop film and never shows a cropped picture. On The Dome Cafe, the phone film is about 4.5 MB for all 80 frames.
Frames and photos are saved as WebP, which is much smaller than older formats at the same quality. Fonts use the compact WOFF2 format, and only the weights the design actually uses.
Casa Fresco's sea and sky are drawn live. Before starting, the site checks the phone: it needs at least four processor cores, enough memory and modern graphics support, with data saver off. Only then does it download the 3D code. Otherwise, the visitor gets still images of the same scene. The sky is also drawn at slightly below full resolution, because a soft sunset doesn't need every pixel, and the animation stops when you switch to another tab.
If a visitor has turned on data saver, or asked their phone for reduced motion, the sites skip the film frames entirely and show still images. They get the same design without the download or the movement.
Holding many large frames in memory can make cheaper phones struggle. Sites check how much memory the phone reports, and on smaller ones keep fewer frames ready at once.
Images further down the page load as the visitor scrolls towards them, and the most important image at the top is fetched first. Menus, hours, reviews and contact details are ordinary text on the page, so they're readable straight away and search engines can read them too.
Speed isn't only about file size. A site also has to stay stable when people do unexpected things. While testing, we found that scrolling back up after the end of one film could crash Chrome, so we changed how frames are kept in memory. On phones with large text settings, a booking form grew wider than its panel, so we fixed the layout. Most of these problems only show up on real phones, which is why we test there.
✅ Try it now: open any site on the showcase on your phone and scroll. Then turn on data saver and open it again to see the still version.
We build it for your business, for free, and check it on real phones before you see the preview.
Request a free website →Related: 3D websites for small businesses · How we build our free 3D websites · Website showcase