# Understanding relevance and ranking ### Search score When performing a search, Search.io assigns a search score to each document in the index. The score ranges from 0 (no match) to 1 (perfect match) and search results are ordered starting with the highest score. The relevance score consists of three score components: the *keyword score,* the *neural score*, and the *boost score*. ![The components of the search score.](https://3882858970-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVeIbtsTcQaqaNeKzLbbU%2Fuploads%2FYG4YS14R8gXyG8pKDTCX%2Fimage.png?alt=media\&token=02e44895-aa08-435d-a209-ebca23f4ed57) ### Relevance The **keyword score** represents the \[[textual-relevance](https://docs.search.io/documentation/fundamentals/search-settings/textual-relevance "mention")]\(textual-relevance) of the result. In other words, how well does the search text match the content. This considers spelling, synonyms, stemming, and other language specific features. The **neural score** represents the neural hash similarity of the result and the search text. The larger of these two scores is used when calculating the overall **search score**, and their contribution generally comprises the majority of the total score, since most users are looking for results which match their query. ### Ranking The **boost score** represents the business-specific ranking of the **search score**. Generally comprising a smaller portion of the total score, it can be used to make [ranking-adjustments](https://docs.search.io/documentation/fundamentals/search-settings/ranking-adjustments "mention") to better tailor results to business requirements or to personalize search results.