SEO visibility is an index metric that estimates how prominently a website appears in organic results across a tracked set of keywords, weighting each ranking by its position and the keyword's search volume. A rising score means your pages are showing up higher, more often, for terms people actually search.
Every SEO tool has its own formula, but the logic is consistent: take a large keyword database, record where your domain ranks for each term, then weight those positions by expected click share and monthly search volume. Ranking #1 for a 40,000-searches term moves the needle far more than ranking #1 for a 200-searches term. The results roll up into a single index you can chart over time. Because the number is relative to a fixed keyword set, it works best as a trend line for one domain, not as an absolute comparison between different tools.
No. Visibility estimates ranking prominence; it doesn't count actual visits. A page can rank well yet earn few clicks when the results page is crowded with ads, AI Overviews, or featured snippets. Treat visibility as a leading indicator, then confirm outcomes with Search Console and analytics.
Usually one of three things: a Google algorithm update reshuffled rankings, the tool changed its keyword set or measurement method, or you genuinely lost positions for high-volume terms. Before reacting, check whether a handful of big keywords caused most of the swing — a single high-volume term can drag the whole index. Pairing the metric with a periodic SEO audit ties movement to concrete causes.