JSON Formatter & Auto-Fixer
NextGenToolkit JSON Formatter is a free, client-side web application that validates, beautifies, repairs broken syntax, and converts JSON into CSV, YAML, TypeScript interfaces, and SQL statements directly in the browser with zero server data transmission.
How to Automatically Fix Broken JSON and Convert It to CSV or TypeScript?
Paste your raw or malformed JSON into NextGenToolkit JSON Formatter, click Auto-Fix Broken JSON to strip trailing commas and repair single quotes via jsonrepair, and switch tabs to export formatted JSON, CSV, YAML, TypeScript Interfaces, or SQL.
How to use JSON Formatter & Auto-Fixer
- Paste JSON or Load Sample Payload: Paste API payloads or broken JSON into the editor or click Load Sample Data.
- Validate or Click Auto-Fix Broken JSON: Inspect exact line/column syntax errors or repair malformed syntax in 1 click.
- Convert to CSV, YAML, TS, or SQL: Switch output mode tabs to copy or download your transformed data.
Technical Specifications
- Execution Engine: V8 JSON AST Parser + jsonrepair Engine
- Supported Formats: Input: JSON / JSON5 / Malformed JSON • Output: JSON, CSV, YAML, TS, SQL
- Privacy Model: 100% Client-Side (API Keys & Payloads Never Leave Browser)
- Batch Support: Multi-Format Export + Instant Minify/Prettify
Semantic Entities & LSI Keywords
RFC 8259 JSON specification · trailing comma & single quote repair · jsonrepair AST parser · JSON to TypeScript interface generator · JSON to CSV RFC 4180 converter · JSON to YAML & SQL CREATE TABLE · line and column syntax error pinning · JSON minifier & beautifier · client-side API payload debugger · beautify json online client side · auto fix invalid json syntax error · convert nested json to csv online · generate typescript interface from json · convert json array to sql insert statements
Frequently asked questions
What syntax errors can "Auto-Fix Broken JSON" repair automatically?
Powered by jsonrepair, it automatically fixes trailing commas, single-quoted strings, unquoted object keys, missing closing brackets, and Python True/False/None constants.
Is it safe to paste production JSON containing API keys or PII?
The JSON formatting and conversion steps run in your browser; the JSON input is not sent to a processing API by this tool.
Can I convert an array of JSON objects directly into a CSV spreadsheet or SQL table?
Yes! Click the CSV or SQL tab in the output toolbar to generate RFC-compliant CSV rows or CREATE TABLE + INSERT statements.
Does it generate TypeScript interfaces from nested JSON?
Yes, select the TypeScript tab to infer strongly typed interfaces from any JSON payload.
What indentation levels are supported?
You can toggle between 2 spaces, 4 spaces, and compact 1-line minified JSON.