JSON Formatter and Validator

Format, validate, and beautify JSON data with syntax highlighting, tree view, and error detection.

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1. Paste your raw or minified JSON data into the input text area. 2. The formatter automatically validates and pretty-prints your JSON with proper indentation. 3. Toggle between the formatted text view and the interactive tree view to explore nested data. 4. Adjust the indentation level using the tab size selector if needed. 5. Review any validation errors highlighted with line numbers and descriptions. 6. Click the copy button to copy the formatted JSON to your clipboard.

About This Tool

The JSON Formatter and Validator is an essential tool for developers working with APIs, configuration files, and data interchange formats. Paste your raw or minified JSON and instantly see it formatted with proper indentation, syntax highlighting, and a collapsible tree view that makes navigating complex nested structures effortless.

Beyond formatting, this tool performs strict validation against the JSON specification, pinpointing exact line numbers and character positions where errors occur. Whether you are debugging a malformed API response, cleaning up a configuration file, or simply trying to read a dense one-liner, this formatter handles it all.

The tree view mode lets you expand and collapse individual nodes, copy specific branches, and understand the structure of your data at a glance. It supports large JSON payloads and provides both compact and pretty-print output options.

Frequently Asked Questions

JSON (JavaScript Object Notation) is a lightweight data interchange format used extensively in web APIs and configuration files. Formatting adds proper indentation and line breaks, making it much easier for humans to read and debug.
This tool identifies and highlights errors in invalid JSON, showing you the exact location and nature of the problem. While it does not auto-correct errors, the detailed error messages help you quickly fix issues like missing commas, unquoted keys, or trailing commas.
This tool processes JSON entirely in your browser, so there is no server-side size limit. It comfortably handles files up to several megabytes. Extremely large files may cause slower rendering of the tree view.
The text view shows your JSON as formatted text with syntax highlighting, which is ideal for copying and pasting. The tree view presents a collapsible, interactive representation of your data structure - perfect for exploring deeply nested objects and arrays.
No. All processing happens entirely in your browser using JavaScript. Your JSON data never leaves your device, making it safe to use with sensitive or proprietary data.

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