Why are Bubble apps slow to load?
Every Bubble page loads Bubble’s shared runtime before it shows your content. Forum tests from November 2024 reported a Lighthouse mobile score of 28 for a Bubble blog page, and about 2.5 seconds and 2 MB transferred for an otherwise blank Bubble page. These are individual tests, not a benchmark. A Bubble app can be optimized, but the runtime sets a floor you don’t control.
How code solves it
Next.js renders pages on the server or at build time, sends only the JavaScript each page needs, and gives you control over images, fonts and caching. It doesn’t guarantee good Core Web Vitals; it gives you the levers to get there.
When Bubble is still fine
Internal tools and dashboards behind a login, where shipping features matters more than the first page load.
Sources: Bubble forum: blog page performance test (November 2024); Bubble forum: page load speed test (November 2024); Google Search Central: Core Web Vitals