Capture
Three viewports, rendered
The page is loaded and photographed at desktop, tablet, and mobile widths. Judgements come from what a visitor actually sees rendered — not from markup, and not from a description of the page.
Methodology
Where the number comes from.
Every claim in a SIGNAL report is tied to something observed on the page. This is the whole procedure, including what it deliberately refuses to do.
Review
47 weighted heuristics
Each capture is checked against the heuristic set for that site type, weighted by how much the category moves a first impression. An e-commerce page is not scored on the same rules as a SaaS marketing site.
Score
Deductions, counted once
The score starts at 100. Every confirmed issue deducts its points once, at its root cause, so a single problem appearing in three places is charged once rather than three times.
Evidence
Unproven claims do not count
Findings without evidence are recorded but never scored. Strengths and manual checks appear throughout for context and cannot raise the number.
The Scoring Model
A score is 100 minus what the issues cost.
Not an average of category grades, and not a model's opinion of your site. Each confirmed issue carries a point value; the report shows exactly which categories those points came from, and they add back up to the difference between your score and 100.
Starting score100
Confirmed issues− points
Signal scorewhat remains
What This Does Not Claim
A method is only credible if it names its own edges.
- We audit what renders publicly. Pages behind a login are out of scope unless you run a product audit.
- A score is a first-impression measure, not a usability study. It cannot tell you what your particular customers will do.
- We do not compare you to an industry benchmark, because we do not have honest data for one yet.