How to format JSON online
- Paste or drop a JSON file. Add JSON text to the editor or drag one
.jsonfile into the workspace. - Check the JSON validator. The right pane displays a formatted preview when the current text is valid JSON. Correct invalid syntax before formatting.
- Review the automatic formatting. Once the JSON is valid, the pretty printer rewrites the source with consistent two-space indentation, ready to copy or download.
Use this JSON Formatter as a simple JSON editor
Use the editable source pane as a lightweight JSON editor: paste, type, replace, or clear JSON, then review the formatted preview alongside it. Whenever the source becomes valid JSON, the pretty-printed result is written back automatically.
This is a JSON syntax validator, not a JSON repair or JSON Schema validation tool. Invalid JSON must be corrected in the source before it can be formatted; the tool does not add missing commas, quote property names, sort keys, or otherwise change data for you.
What JSON formatting changes
Two-space JSON pretty printing
Formatting changes whitespace only. It adds predictable two-space indentation and line breaks around objects and arrays, making minified or inconsistently indented JSON easier to read.
Formatting does not transform JSON data
The formatter does not rename keys, change numbers, or alter the JSON data structure. It does not offer key sorting; it formats only valid JSON with the property order produced by the browser's JSON parser.
Why use a browser JSON Formatter and editor?
JSON beautifier with fixed indentation
Use consistent two-space indentation to make API responses, configuration files, and fixtures easier to review.
JSON validator while you edit
Check JSON syntax before you copy the document into an API, configuration file, or JSON converter.
Local processing
Parsing, previewing, and formatting run in the browser without a server request for those actions.
Formatted preview
See syntax-coloured keys, strings, numbers and literal values beside the editable source.
JSON Formatter or JSON Viewer?
| Your goal | Best tool |
|---|---|
| Edit, validate, and pretty print valid JSON | Use this JSON Formatter. |
| Explore objects and arrays in a collapsible tree | Use the JSON Viewer. |
| Turn JSON records into a spreadsheet-friendly file | Use JSON to CSV or JSON to Excel after checking the source. |
What happens to your JSON?
Typing, pasting, parsing, previewing, and formatting occur in your browser. The JSON Formatter does not make a server request for those actions.
Use a private window or remove sensitive values before sharing your screen. Browser extensions and other software on your device are outside the formatter's control.
Working Smoothly with Multi-Gigabyte Files
SolConverter is built to keep multi-gigabyte files moving without freezing the workspace. It processes source data in manageable chunks, keeps the on-screen preview lightweight, and lets you download the completed artifact without loading the entire result at once.
Uploads, conversion, and previews remain responsive as file sizes grow. Background processing and progressive progress updates handle the heavy work, so you can work with multi-GB source files while keeping the browser workspace usable.
JSON Formatter FAQ
What does a JSON Formatter do?
A JSON Formatter, also called a JSON pretty printer or JSON beautifier, validates a document's syntax and rewrites valid JSON with predictable indentation and line breaks.
Can I use this as a JSON editor?
Yes. The source pane is editable, so you can paste, type, and replace JSON before formatting it. It is a simple text editor for JSON, not a tree editor or a JSON repair tool.
Is this a JSON validator?
Yes, for JSON syntax. The preview shows when the current source is valid JSON. It does not validate a document against a JSON Schema.
Does formatting change JSON data?
No. It changes whitespace for readability; keys and values are not changed. This simple formatter does not offer key sorting.
Can I format a JSON file?
Yes. Drop one .json file into the workspace. It is formatted automatically after it loads and validates.
Is my JSON uploaded?
No. JSON parsing, previewing, and formatting run locally in your browser. The formatter does not make a server request for those actions.
Why will the formatter not run?
The document must be valid JSON. Correct the syntax in the editable source, then run the formatter. It does not repair invalid JSON automatically.