A data normalization rule is a predefined guideline that standardizes CRM data fields and structures to improve accuracy and consistency. Normalization ensures that data is stored in a structured, uniform format to prevent inconsistencies. For example, a CRM may enforce a rule that all phone numbers include a country code, reducing formatting errors. Normalization improves data interoperability, reporting accuracy, and integration efficiency. Businesses implement AI-powered data cleansing tools to automate normalization and maintain high data quality.