v0 is Vercel’s AI builder: you describe an interface or an app, it writes a Next.js project, and you can deploy it to Vercel from the same window. Its sites are among the easier ones to recognise, because v0 writes its name into the page it starts from and into the address it deploys to. In our accuracy test we name v0 on all 25 of the v0 sites in our labelled set.
Here are the traces we look for.
1. A generator tag
Near the top of the source (Ctrl+U), a page v0 started often says so:
<meta name="generator" content="v0.app" />
Older projects say v0.dev, v0’s earlier address. A generator tag names the tool that produced a page, and owners rarely remove it.
2. A default description and title
An untouched v0 project describes itself as “Created with v0” in its meta description, and newer ones keep the title “v0 App”. Owners often change the visible text of a page and forget these two, which are the words search results and link previews show.
3. A preview address
While you work in v0, it shows your app at a preview address ending in .vusercontent.net. Those previews are public, and so are pages saved from them: a copy of a preview still loads its files from vusercontent.net. Search the source for vusercontent.
4. A deploy name, with a Next.js build
When v0 deploys a project to Vercel, it names it after the chat that made it, starting with v0-, so the site’s first address reads like v0-portfolio-site.vercel.app. Someone could name a project that way by hand, so we count the name only together with the Next.js build v0 writes, and rate it Medium, never High.
How sure can you be?
Traces 1 to 3 are v0’s own, and any one of them is a builder signature: we rate the AI traces High. The deploy name is weaker, and says so.
The reverse doesn’t hold. A v0 project moved to its own domain, with its metadata rewritten, looks like any other Next.js site, and “none found” is never proof that a site wasn’t made with v0 or with any AI tool. v0 projects also often use shadcn/ui components and Lucide icons, but so do countless sites built by hand, so we list those only as context.
And being made with v0 says nothing about whether a business is honest. It’s a fact about how a site was built, not a judgement of the people behind it.
Check any site for these traces at once: the AI Website Detector shows each one it finds, with the exact line from the page.