Why did Wappalyzer find fewer technologies for a website?
The Wappalyzer help pages give 3 common reasons. The first to rule out: When a lookup has to crawl a site, its first response holds no technologies, and the full results arrive later.
What causes it?
When a lookup has to crawl a site, its first response holds no technologies, and the full results arrive later.
In the Wappalyzer help:
Requests will always invoke a crawl and the initial responses do not return any technologies.
Technology lookup - Wappalyzer, read 2026-11-12.Wappalyzer only adds technologies with clear public signals and an established user base, so a niche or hidden tool may not be detected.
In the Wappalyzer help:
We only accept web technologies with clear public web signals and an established user base.
Frequently asked questions - Wappalyzer, read 2026-11-12.By default a lookup returns results from Wappalyzer's database, which it describes as more complete, so a live analysis of the same site can show a different set.
In the Wappalyzer help:
Defaults to false to return cached results from our database (faster and more complete).
Technology lookup - Wappalyzer, read 2026-11-12.
How do I check it myself?
Make sure you keep both the first response and the later one, since the full set of technologies comes from both.
In the Wappalyzer help:
Capture both the initial response and the callback response if you want the full result set.
Technology lookup - Wappalyzer, read 2026-11-12.If a crawl is still running, wait and ask again a few times before treating the result as fewer technologies.
In the Wappalyzer help:
We recommend using callback_url or repeating the request up to three times every five minutes.
Technology lookup - Wappalyzer, read 2026-11-12.
How does Wappalyzer work with Feder?
- Connect Wappalyzer to Feder and it joins your Interest apps.
- When you connect Wappalyzer, Feder checks the connection straight away and shows Connected only when that check passes. If a reading cannot be taken later, Feder shows it as not read, never as zero.
Some numbers are too quiet to judge daily, such as a form filled in a few times a week. Until there is enough of your own history to judge a change, Feder says it is still learning and scores nothing, rather than guessing.
See whether you can trust the numbers in Wappalyzer, one of your Interest apps. Feder only reads. It never changes anything in Wappalyzer.
What else goes wrong with these numbers?
- Why does Wappalyzer list technologies a website doesn't seem to use?Wappalyzer
- Why did Google Analytics stop collecting data?Google Analytics
- Why aren't my key events showing in Google Analytics?Google Analytics
- Why does Google Analytics show (not set)?Google Analytics
- Why is yesterday's data missing in Google Analytics?Google Analytics
See every question.
Where do these answers come from?
Every cause and check on this page comes from the Wappalyzer help pages, quoted above with the date we read them. Last reviewed 2026-11-12. We read them again by 2027-11-12. If one changes, this page changes or comes down.