JSON Formatter & Validator
Beautify hard-to-read JSON or YAML.
Tree view supported. 100% secure local processing.
⚠️ Parse Error
🔒Data is securely processed in your browser.
About JSON Formatter & Validator
The JSON Formatter & Validator is a free developer tool designed to prettify hard-to-read single-line JSON or deeply nested JSON data into a clean, human-readable format.
It features options to change indentation (2 spaces, 4 spaces), minify JSON to remove unnecessary spaces, real-time syntax validation with error notification, two-way conversion between YAML and JSON, and an intuitive Tree View display. It has all the essential features developers need.
How to Use
Input Data
Paste the JSON (or YAML) you want to format or validate into the left input area.
Select Action
Click the desired action button like "Format (2 Spaces)" or "Convert to YAML".
Check Result
The result will be displayed in the right output area. Warnings will appear if there are errors.
Tree View
Switch to the Tree View tab to visually explore the hierarchical structure.
JSON / YAML Glossary
- JSON (JavaScript Object Notation)
- A lightweight data-interchange format, globally recognized and widely used for API responses and configuration files.
- YAML (YAML Ain't Markup Language)
- A human-friendly data serialization standard. It uses indentation to represent hierarchy and is common in CI/CD config files.
- Validation
- The process of verifying whether the input JSON string follows standard syntax rules (e.g., no missing commas).
- Minify
- The process of removing all unnecessary line breaks, spaces, and indents from JSON to create a compact single-line string, reducing data size.
- Tree View
- A UI representation that displays hierarchical data in an expandable/collapsible tree-like structure, similar to folders and files.
Frequently Asked Questions
- Q.Is the entered JSON data saved on the server?
- No. Data parsing and formatting are executed entirely on your browser (JavaScript). Your data is never sent to or stored on external servers.
- Q.It shows an error and cannot be formatted.
- If there are JSON syntax errors (such as a trailing comma, using single quotes, or missing double quotes around keys), parsing will fail according to standard specifications. Please use the error message to fix it.
- Q.Can I convert YAML data?
- Yes. Just paste YAML formatted data into the input area and click the "Format" button. It will be automatically parsed and output as formatted JSON.
- Q.Can I expand all levels in the Tree View at once?
- Currently, you can expand level by level by clicking the parent nodes. We plan to add "Expand All" and "Collapse All" buttons in a future update.
Use Cases
API Response Analysis
Format and analyze single-line JSON responses retrieved from browser Developer Tools (Network tab) or cURL commands.
Config File Validation
Prevent syntax errors like missing commas when creating or editing package.json or application config files by using this tool for validation.
YAML-JSON Conversion
Quickly convert data written in YAML format (like Kubernetes manifests or Swagger definitions) to JSON format, or vice versa.
Documentation Support
Standardize formatting (e.g., 2 spaces) when including JSON code samples in API specs or technical documentation.
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