--- layout: docs page_title: Transform description: >- Part of Vault's Advanced Data Protection solution, protecting sensitive information stored outside of Vault. --- # Transform Secrets Engine Part of Vault's Advanced Data Protection solutions, Transform provides mechanisms for _transforming_ sensitive information to protect it even as it lives outside Vault's sphere. Transform consists of three modes, called _transformations_. Format Preserving Encryption (**FPE**) for encrypting and decrypting values while retaining their formats. **Masking** for replacing sensitive information with masking characters. And **Tokenization** which replaces sensitive information with mathematically unrelated tokens. ## Comparison to Transit Transit implements many traditional cryptographic primitives, such as AES encryption and RSA signatures (among others). Transform implements solutions to protect sensitive values in more narrow, but still critical use cases. ## What Solution When? When should one use a particular transform or transit encryption? Based on your use case and its requirements, this flowchart can help you choose the right solution. ![Transit vs Transform](/img/transit-or-transform.png) Keep in mind that unlike all other solutions, Tokenization is stateful, and all values must be stored either within Vault or a supported external store. As such all other solutions will outperform and outscale tokenization.