Lovable, v0 and Bolt websites: what gives them away.
Every AI builder leaves fingerprints: the domain, the fonts, the stock colors, even the CSS variable names. Most of them come off in an afternoon.
Lovable, v0 and Bolt do similar things, but not the same things. Each one starts from a different base and gives the model different instructions, and it shows. If you've seen enough of their sites, you can tell which one was used in a few seconds.
This isn't about calling anyone out. It's the checklist worth running before you launch. We put it together from real sites while building the Slop Score, which looks for these fingerprints automatically.
What all three have in common
- Tailwind and shadcn/ui with stock values: near-black text, mid-gray secondary text, a light gray border and the same radius on every corner.
- Lucide icons on every card, every list item and sometimes as the logo.
- A `<title>` that's the project name, lowercase and hyphenated, instead of your business name.
- Images named after their section:
hero-image,feature-1,testimonial-avatar. - The same page structure: centered hero, three benefits, how it works in three steps, testimonials, pricing, FAQ and a closing call to action.
Lovable
Lovable generates a design system with very recognizable variable names: --primary-glow, --gradient-primary, --shadow-elegant or --transition-smooth. If two or more show up in your CSS, it almost certainly came from Lovable, even on a custom domain.
Other fingerprints: a lovable.app or lovableproject.com domain, images uploaded under /lovable-uploads/, the "Edit with Lovable" badge on plans that show it, and the same transition on everything that moves.
How to remove it: connect your own domain, rename the variables or ask it to rewrite the design system with your values, and replace the "elegant" gradients and shadows with a decision of your own.
v0
v0 comes from Vercel and it shows: Geist and Geist Mono as the only typefaces, the stock shadcn theme and a near black-and-white palette with one accent. It's the most restrained of the three, which is why people assume it has no slop. It does: it's the same for everyone.
How to remove it: change at least the heading typeface, define your own colors across the theme variables (not just primary) and change the corner radius. Three changes and the site stops looking like a component demo.
Bolt
Bolt builds Vite projects with React, Tailwind and Lucide, and publishes to bolt.host. Its sites tend to have more color than v0's and more sections than the project needs, with stock photos in the hero.
How to remove it: publish on your own domain, cut sections (if you have no testimonials or pricing, leave them out) and replace stock photos with something of yours.
What you can't see but can find
Some fingerprints aren't on screen but in the code: comments like <!-- Hero Section -->, Tailwind loaded from its CDN in production, or a robots.txt that returns the homepage. Visitors won't notice, but search engines and anyone who knows where to look will.
None of these sinks you on its own. But when the whole site says "the generator made this and nobody checked", people project that onto your product.
Where to start
- Your own domain, a
<title>and description you wrote, and your favicon. - Heading typeface and color: they're the most visible.
- Sections the generator added just because.
- The code fingerprints, once everything else is done.
For each change, the prompts guide has one ready to paste into the same builder.
Frequently asked questions
How can you tell if a website was made with Lovable?
Look for a lovable.app domain, images under /lovable-uploads/ or CSS variables like --primary-glow, --gradient-primary and --shadow-elegant. Two or more of those variables together almost always come from Lovable, even on a custom domain.
How can you tell if a website was made with v0?
It usually uses only Geist and Geist Mono, the untouched shadcn/ui theme and a near black-and-white palette. Those three together are v0's baseline.
Does Google penalize AI-generated websites?
Google says it judges how useful content is, not how it was made. The problem with a generic site isn't a penalty: it's that people leave before reading it and nobody links to it.
Should I stop using Lovable, v0 or Bolt?
No. They're good tools for getting to something that works, fast. Just make the design decisions yourself and remove the fingerprints before you launch.