Data cleansing (also known as data scrubbing) is the name of a process of correcting and if necessary eliminating inaccurate records from a particular database. The purpose of data cleansing is to detect so called dirty data (incorrect, irrelevant or incomplete parts of the data) to either modify or delete it to ensure that a given set of data is accurate and consistent with other sets in the system.

Manual data cleansing is usually done by persons who read through a set of records for verification of accuracy of these, correct spelling errors and complete missing entries. During this operation some unnecessary or unwanted data is removed in order to increase efficiency of data processing.