SimpleSchema validates JavaScript objects to ensure they match a schema. It can also clean the objects to automatically convert types, remove unsupported properties, and add automatic values such that the object is then more likely to pass validation.

There are a lot of similar packages for validating objects. These are some of the features of this package that might be good reasons to choose this one over another:

• Isomorphic. Works in NodeJS and modern browsers.
• The object you validate can be a MongoDB modifier. SimpleSchema understands how to properly validate it such that the object in the database, after undergoing modification, will be valid.
• Optional Tracker reactivity for Meteor apps
• Powerful customizable error message system with decent English language defaults and support for localization, which makes it easy to drop this package in and display the validation error messages to end users.
• Recommended by MDG, the group that makes Meteor
• Has hundreds of tests and is used in production apps of various sizes
• Used by the Collection2 and AutoForm Meteor packages.