C# Interview Question #117
What is the difference between System.Text.Json and Newtonsoft.Json?
Concurrency, Performance & Design Senior Advanced
Quick Interview Answer
System.Text.Json is built into modern .NET and is optimized for performance, low allocations, and integration with ASP.NET Core. It is the default JSON serializer for current ASP.NET Core applications.
Detailed Explanation
System.Text.Json is built into modern .NET and is optimized for performance, low allocations, and integration with ASP.NET Core. It is the default JSON serializer for current ASP.NET Core applications.
Newtonsoft.Json, also known as Json.NET, is a mature third-party library with a large feature set and remains useful for compatibility or specialized serialization scenarios.
For new applications, System.Text.Json is usually the default choice unless a required feature or existing contract specifically favors Newtonsoft.Json.