JSON Formatter and Validator
Use JSON Formatter and Validator
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Input
About this tool
Format, validate, repair, search, and inspect JSON in a cleaner editor built for developers, APIs, and configuration files.
- 100% free with no usage limits
- No sign-up or login required
- Runs right in your browser
- Privacy-friendly and fast to use
Docs
Format, validate, repair, search, and inspect JSON in a cleaner editor built for developers, APIs, and configuration files.
JSON Formatter & Validator User Guide
1. Overview
This is a clean and professional online JSON processing tool. Core capabilities include:
- Formatting (Pretty Print): turn minified or messy JSON into clear, indented structure.
- Compacting: remove extra spaces and line breaks to produce a single-line JSON string for transmission efficiency.
- Validation: check whether JSON syntax is valid and report errors.
- Repair: try to auto-fix common JSON issues such as missing quotes or trailing commas.
- Transform and Query: in Advanced Mode, transform data and run queries on JSON.
- View Switching: in Advanced Mode, switch between text view and table view for easier inspection.
- Schema Validation: in Advanced Mode, validate data shape with JSON Schema.
- Quick Actions: copy output with one click and download as file.
2. Quick Start
Input JSON
- Drag and drop a
.jsonfile into the tool area. - Or paste your JSON into the input editor.
Run Actions
- Click “Format” to output readable JSON.
- Click “Compact” to generate single-line JSON.
- The tool validates content and reports problems when syntax is invalid.
Use Output
- Click “Copy” to copy the result to clipboard.
- Click “Download” to save the result as a
.jsonfile.
3. Core Features
3.1 Basic Features
| Button | Description |
|---|---|
| Format / Pretty | Indents JSON by hierarchy (commonly 2 or 4 spaces) to improve readability and editing. |
| Compact | Removes line breaks and extra spaces to produce compact one-line JSON, useful for API payloads and storage optimization. |
| Copy | Copies the current processed output to the system clipboard. |
| Download | Exports the current result as a local .json file. |
| Auto Repair | Attempts to fix non-fatal issues (for example, unquoted property names or trailing commas). Severe structural errors still require manual fixes. |
3.2 Advanced Mode
After enabling “Advanced Mode”, extra capabilities appear:
- Text / Table Views:
- Text View: standard code-style JSON view.
- Table View: renders JSON data (especially object arrays) in rows and columns for quick reading.
- Transform: process data such as filtering array items, selecting fields, or modifying values.
- Query: extract target data from complex JSON structures with query syntax.
- Schema Validation: paste a JSON Schema and validate whether current data matches required structure, types, and constraints.
4. FAQ & Tips
Q1: When should I use “Auto Repair”?
Use it when JSON is invalid due to small formatting mistakes.
Example: {name: "John"} should be {"name": "John"}.
Q2: What are table view limitations?
Table view works best for arrays of objects with similar structure. For deeply nested or inconsistent JSON, switch back to text view.
Q3: How can I validate against API requirements?
- Get the JSON Schema from API documentation.
- Open Schema validation in Advanced Mode and paste the schema.
- Paste your JSON data and review validation results.
Q4: Will my data be leaked?
The tool is typically processed in the browser. For security, avoid pasting production secrets such as passwords, tokens, and private keys.
FAQ
Is it free?
Yes, completely free. No signup, no limits.
What features?
Format/beautify, minify, validate, auto-fix errors, copy, download.
Will data be uploaded?
No. All local; nothing leaves your computer.
Can it auto-fix?
Yes. Detects and fixes missing quotes, trailing commas, etc.
Max file size?
Large JSON (>10MB) may lag. Process in batches.
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