Next.js Detector
Paste any URL and instantly see whether the site is built with Next.js — with the matched evidence.
We do not store the URL you audit. Want the full audit (performance / images / SEO / accessibility + real-browser speed test)? → run the full audit
Why check this
Next.js performance depends on rendering mode (SSR/SSG/ISR) and image components. Confirming the framework is step one.
What this is
Next.js is the React meta-framework behind a large share of marketing sites and product apps. Its fingerprints sit in asset paths and page payloads, and confirming it tells you whether the fixes belong in the image component, in route caching or in the client bundle.
How to tell from a public page
- Asset paths under /_next/static/ or /_next/image appear in HTML and CSS.
- A __NEXT_DATA__ script tag, or app-router flight data in self.__next_f, is present.
- Headers or build artefacts reference x-nextjs-* or x-powered-by: Next.js.
- Links prefetch route payloads before a visitor clicks anything.
How to read the result
Any one of the structural signals above means confirmed. Misses are normal for static exports and for sites that rewrite asset paths through their own CDN host; a passing mention in a blog post is only suspected. Common false positive: tutorial code blocks that ship __NEXT_DATA__ in a demo page.
What to do next
Check the rendering mode per route, next/image sizing, and third-party scripts mounted in the root layout — those three cover most of the score. Hosting clues usually point at Vercel detector. For weighted LCP, image, SEO and accessibility scores, run the full audit at run the full performance / images / SEO / accessibility audit on the home page.
Related detectors
FAQ
How is Next.js detected?
From structural signatures in the public HTML and response headers (domains, paths, attributes, scripts). Every verdict lists how many times each pattern matched — nothing is guessed.
Can the result be wrong?
If only a bare brand keyword matches without structural evidence, we label it \u201clikely\u201d instead of \u201cconfirmed\u201d — we would rather under-report than cry wolf.
Do you save the URLs I check?
No. The audit runs inside the request and the URL you paste is not written to storage. There are no third-party tracking scripts on the page either, so no log of who checked what exists. Copy the result yourself if you want a record.
Can a website hide what it is built with?
Partly, but rarely completely. The HTML sent to your browser, the response headers, script paths and asset structure have to be exposed to work, so there is always something readable. Server-side code, build config and private APIs stay invisible. That is why this tool reports the evidence it found rather than claiming a full picture. No match does not mean the technology is absent.
Optimization help is available
Tell me your URL and what you want fixed — you get a clear scope, price and timeline.
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