JSON

Lesson in the Flutter Roadmap · Stage 9: Working with APIs

Last updated 14 September 2026

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write and easy for machines to parse and generate. In Flutter, JSON is used for transmitting data between the client and server, typically over an HTTP connection.

Flutter provides a number of libraries for working with JSON data, including the dart:convert library, which provides support for encoding and decoding JSON data.

To encode a Dart object to a JSON string, you can use the jsonEncode function from the dart:convert library. To decode a JSON string to a Dart object, you can use the jsonDecode function.

Study this in the interactive course See the whole Flutter roadmap

Free resources to learn JSON

Official docsJSON and serialization
Official docsUsing JSON

JSON: common questions

Can I learn JSON in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain JSON in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this JSON tutorial for beginners?

It is lesson 39 of 108 in the free Flutter roadmap, in stage 9, Working with APIs. If you are new to Flutter, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.