How the site health score works
How SiteAud!tLint turns issues into 0 to 100 category scores and an overall site health score, and why one broken page still costs points.
Site health is a number from 0 to 100 shown in the header, on Overview and at the top of the HTML report. It is built from category scores, and each category score is built from the issues found in it.
Category scores
Every issue type found in a category costs a fixed amount for being present at all, plus an extra amount based on the share of crawled pages it affects:
| Severity | Fixed cost | Extra cost at 100% of pages |
|---|---|---|
| Critical | 8 points | 25 points |
| Warning | 3 points | 12 points |
| Opportunity | 0.5 points | 4 points |
| Info | 0 | 0 |
So one broken page on a 1,000 page site still costs about 8 points, while cosmetic opportunities barely move the score. This is deliberate: a single 404 in your main navigation matters more than its share of pages suggests.
Overall site health
The overall score is a weighted average of the category scores. Technical SEO and On-Page SEO weigh the most:
| Category | Weight |
|---|---|
| Technical SEO | 1.5 |
| On-Page SEO | 1.2 |
| Content, Internal Linking, Performance, Security | 1.0 |
| AEO / GEO | 0.8 |
| Accessibility | 0.7 |
| Images, Structured Data | 0.6 |
Then 3 points are taken off for every distinct critical issue type, up to 15 points. A site with critical problems cannot score in the high 90s, however good the rest is.
Tracking has its own score
Issues in the Tracking & Analytics category, such as a GA4 tag loaded twice, get a separate Tracking score. They never lower SEO site health. See Tracking and pixels audit.
Why the score changed
The header shows the change since the previous audit of the same site. To see exactly why, open Compare for new and fixed issues, or Site Health > Before and After to compare 20 metrics side by side.
A score can also drop without anything breaking: if the site grew, or the previous audit stopped at a page limit, the new audit may simply have reached pages the old one never checked.
Frequently asked questions
Why does my site show no score?
When no page could be read (every request failed or was rate limited), no score is shown instead of a misleading "Good". Check the audit is incomplete.
Is a score of 100 possible?
Yes, when no critical, warning or opportunity issues are found. Info notices never lower the score.
Applies to SiteAud!tLint 0.3 and later. Current version 0.7.1.