Every technology we detect on a website is given a Confidence Score from 0 to 1 — or 0% to 100% — along with a simple Low, Medium or High confidence rating. This tells you how confident we are that a detection is accurate and current. A High score means we're confident in the detection, while Medium or Low means there are reasons to treat it with more caution. The score makes it easier to distinguish strong, repeatedly confirmed technology signals from detections that may be older, less reliable or harder to verify.

Confidence score is also available in the Domain API v25.

🔍 There are several reasons confidence may be reduced. If a site shows signs of being a scam or contains gambling content, we lower the confidence of most technology detections because these sites can contain leftover or misleading signals; core infrastructure such as hosting, mail providers and registrar information is unaffected. Confidence can also be reduced when a domain appears to be parked, when a technology has only been detected once, or when an older technology hasn't been seen recently and appears to have been replaced by something newer. The longer ago a technology was detected and the stronger the evidence that it has been replaced, the lower its confidence becomes — although age alone will never reduce a detection all the way to zero. Certain business or operational intelligence data points follow a different verification process and are assigned a fixed confidence of 50%.

📊 To make the score easy to interpret, detections are also grouped into Low, Medium and High confidence. High indicates a strong technology detection, while Medium and Low indicate increasing levels of uncertainty based on the factors above. A fixed 50% score identifies business or operational data rather than a standard technology detection, while a score approaching 0% means there are substantial reasons to question the detection. ⚠️ Confidence Scores provide an additional layer of context to BuiltWith data, allowing you to quickly understand which detections have the strongest supporting evidence and which deserve a little more caution.