Glossary
Visibility Index
A Visibility Index is a composite SEO metric that quantifies how visible a website is in organic search results across a defined set of tracked keywords, expressed as a percentage or absolute score. Unlike individual keyword rankings — which tell you where you stand for a single query — a Visibility Index aggregates thousands of tracked keywords, weights each by its position (higher positions contribute more) and search volume, and produces a single number that trends up or down over time. It is the primary high-level diagnostic for domain-wide organic performance: a rising index means your content strategy is gaining ground; a flat or falling index signals competitive erosion, algorithm impacts, or content decay. Major SEO platforms each compute their own visibility indexes with slightly different keyword universes and weighting methodologies, so cross-tool comparisons should compare trends rather than absolute values. For SEO practitioners, the Visibility Index answers the question 'are we becoming more or less visible to our target audience in search?' without getting lost in the noise of individual ranking fluctuations.