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The #1 Free JSON Tool
Master Your { JSON Data }
Best Online JSON Formatter, Type Generator, Visualization and API Schema Checker
Format, Repair, and Validate your JSON data instantly. The ultimate developer toolkit.
JSON Formatter
Repair, Validate & Format JSON
Format JSON
Visualizer
Visualize Data as Graph,Flowchart, Tree and Table view
Visualize
API Monitor
Monitor your API Health, get alerts when api schema change
Monitor
JSON Path
Evaluate JSONPath Queries
Evaluate
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Converters, Generators & Validators
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Recent Updates
- Added Share & Connect card to explore tools and connect
- Search functionality in JSON Visualizer
- Integrated Talk to JSON feature
- Table View support in JSON Visualizer
- Visualizer support for CSV, YAML, XML, TOON
- JSONPath support in home page visualization
- Download diagram in visualization
Last updated: Jan 26, 2026
Visualizer Use Case #1
API Design
Visualize API structures and response patterns clearly during the design phase.
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JSON Guides & Tutorials
Master JSON with our comprehensive guides, best practices, and optimization techniques.
Common JSON Questions
Find answers to frequently asked questions
What is JSON and how does it work?
What are JSON files and how to open them?
What is a JSON Parser and why is it needed?
What does the JSON syntax with square brackets represent?
How is JSON used in financial compliance reporting?
What are the rules of JSON syntax?
What are JSON files?
What are some applications of JSON?
What are the benefits of using JSON?
What is a JSON String?
What is the function of JSON.stringify?
What are JSON objects?
What are the applications of JSON?
What advantages does JSON have over XML?
What is the purpose of a JSON Validator?
How do you convert a JSON text to a JavaScript object?
What is JSON Formatter and how does it work?
What is the JSON file's extension?
What is the purpose of using JSON in Python?
Explain JSONP.
What is JSON's MIME type?
What is JSON?
What are some widely used JSON libraries in .NET?
In JavaScript, what is JSON?
What steps are involved in converting a string to a JSON Array?
What is JSON Schema?
Which browsers support JSON?
Why is JSON used in Android?
Why is JSON used in PHP?
Can comments be added to a JSON file?
Explain JSON RPC and JSON Parser.
What is the purpose of the Newtonsoft Net framework?
What are the data types supported by JSON?
What are the limitations of JSONP?
Which function is used to turn a JSON string into an object?
Do all programming languages and platforms support JSON?
Differentiate between JSON and JSONP
Describe the benefits and characteristics of JSON.
What is a JSON Viewer?
Why use JSON instead of XML?
Mention the PHP function used to encode JSON.
What are the disadvantages of JSON?
What do JSON and XML have in common?
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External Documentation
Trusted documentation and resources for JSON standards and best practices.
Why use our JSON Formatter?
JSON Formatter & Validator by JSONMaster is the ultimate tool for developers to format JSON, validate JSON, and beautify JSON data instantly. Whether you are debugging an API response or cleaning up configuration files, our tool helps you:
- Format JSON: Convert minified or ugly JSON into a readable, tree-structured format with proper indentation.
- Validate JSON: Detect syntax errors like missing commas, brackets, or quotes with line descriptions.
- Fix JSON: Automatically repair common JSON errors using our intelligent JSON Repair feature.
- Minify JSON: Compress your JSON data to save space for production usage.
Our tool runs entirely in your browser, ensuring your data remains private and secure. Use JSONMaster for all your JSONLint needs and experience the fastest online JSON Viewer.
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Meet the Developer
Hi, I'm Yutilo
I am the solo developer behind JSONMaster. My passion lies in building usable, high-quality tools that solve real problems for developers. I believe that good software should be intuitive, fast, and accessible to everyone.
I created this website to provide a comprehensive, all-in-one toolkit for working with JSON data. I hope you find it useful for your daily tasks. If you have any feedback or suggestions, please feel free to reach out connect with me!