Techniques for visual data preparation are described. An interactive visual data preparation service provides a user with a graphical user interface that presents values from a sample taken of a dataset along with statistical information associated with those values. A user uses the graphical user interface to test out various transformations to the sample dataset by applying transformations and viewing near-immediate results of those transformations as applied to the sample. The desired set of transformations is represented as a recipe object, which can be used to perform data preparation against the overall dataset or other datasets on behalf of the user or other users.