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JSONLint

JSONLint is a free online validator and formatter for JSON, allowing users to validate, format, and beautify JSON code through copy-paste or URL input.

Published: 2025/12/19

Introduction

JSONLint is a web-based tool designed to validate and format JSON (JavaScript Object Notation) data. It allows users to input JSON code directly, paste it from the clipboard, or provide a URL containing JSON data. The tool then checks the JSON for syntax errors and formats it for improved readability.

Key Features:

  • JSON Validation: Checks JSON code for syntax errors and adherence to JSON standards.
  • JSON Formatting: Beautifies JSON code by adding indentation and line breaks for improved readability.
  • URL Input: Allows users to validate JSON data directly from a URL.
  • Copy-Paste Input: Supports direct input of JSON code via copy and paste.
  • Error Detection: Identifies and highlights specific errors in the JSON code, including line numbers.
  • Compression/Minification: Can compress JSON to reduce file size.

Use Cases:

  • Software Development: Validating JSON data used in APIs, configuration files, and data exchange.
  • Data Analysis: Formatting and validating JSON data extracted from various sources.
  • Web Development: Ensuring the correctness of JSON data used in web applications.
  • Educational Purposes: Learning and understanding JSON syntax and structure.
  • Troubleshooting: Identifying and resolving errors in JSON code.

JSONLint simplifies the process of working with JSON data by providing a user-friendly interface for validation and formatting, making it an essential tool for developers and data professionals.

Alternatives

  • JSON Formatter & Validator (Code Beautify)

    This online tool offers similar JSON validation, formatting, and beautification capabilities directly in your browser.

  • JSON Editor Online

    It provides an interactive editor for JSON data, allowing users to validate, format, and edit JSON in a tree or code view.

  • Visual Studio Code

    A powerful code editor with built-in JSON support, including formatting, validation, and schema-based linting for local files.

  • Postman

    Primarily an API development environment, Postman includes excellent JSON viewing, formatting, and validation features for API responses.

  • jq

    A lightweight and flexible command-line JSON processor that can be used for parsing, filtering, mapping, and transforming JSON data, including validation.

  • Insomnia

    Similar to Postman, this API client offers robust JSON handling, including formatting and syntax highlighting for requests and responses.

  • JSON Viewer Pro (Browser Extension)

    This browser extension automatically formats and validates JSON directly within your browser window when you open a JSON file or API response.

  • Sublime Text

    A sophisticated text editor that, with appropriate packages, provides advanced JSON formatting and linting capabilities for developers.

  • Notepad++

    A popular free source code editor for Windows that can be extended with plugins to offer JSON formatting and validation functionalities.

  • JSON.tools

    This website offers a collection of various online JSON utilities, including validators, formatters, and converters, providing a broader suite of tools.

User Reviews

4.0/5.0
(17reviews)
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Pricing

Pricing Model: Free

Free

JSONLint is a free online validator, formatter, and beautifier tool for JSON, a lightweight data-interchange format. It helps tidy and validate messy JSON code.

Free
N/A

FAQ

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