How do I validate JSON online?

Paste your JSON into the input field and select 'Validate' mode. The tool instantly checks syntax and reports any errors with the line number and column where the issue occurs. Valid JSON is also pretty-printed for easy reading.

What are common JSON syntax errors?

The most common mistakes are: trailing commas after the last item, using single quotes instead of double quotes, unquoted property names, including comments (JSON doesn't support // or /* */), and missing commas between key-value pairs.

How do I convert JSON to CSV?

Paste a JSON array of objects into the input field and select 'JSON → CSV' mode. The tool extracts all unique keys as column headers and converts each object into a row. Nested objects are serialized as JSON strings in the CSV output.

What is the difference between JSON and YAML?

JSON uses braces, brackets, and double quotes with strict syntax. YAML uses indentation instead of braces, supports comments, and is more human-readable. YAML is preferred for configuration files (Kubernetes, Docker Compose, CI/CD), while JSON dominates web APIs.

Can I minify JSON to reduce file size?

Yes. Select 'Minify' mode to remove all whitespace, line breaks, and formatting from your JSON. This typically reduces file size by 30–60% without changing the data, making it ideal for production APIs and storage optimization.

How do I convert CSV to JSON?

Select 'CSV → JSON' mode and paste your CSV data. The first row is used as object keys (headers), and each subsequent row becomes a JSON object. All cell values are preserved as strings to avoid data loss with identifiers, zip codes, or large numbers.

Is my data stored or sent to a server?

No. All conversion and formatting happens entirely in your browser using JavaScript. Your data never leaves your device — it is not stored, logged, or transmitted to any server. Your input text is never written to the URL or browser history, so it is safe to paste API keys, tokens, or other sensitive data.

JSON Converter

Mode

Indentation

JSON Input

10 lines177 chars177 bytes

Format / Beautify Output

{
  "name": "Ganak",
  "version": "1.0",
  "features": [
    "calculators",
    "converters",
    "tools"
  ],
  "config": {
    "theme": "dark",
    "language": "en",
    "maxItems": 100
  }
}

14 lines · 193 B

JSON Statistics

177 B input · 7 keys · depth 2

Keys

Depth

Objects

Arrays

Strings

Numbers

Booleans

Nulls

What Is a JSON Converter?

A free tool to format, validate, and convert JSON data between multiple formats

JSON (JavaScript Object Notation) is the most widely used data interchange format on the web. This converter lets you format JSON for readability, minify it for production, validate syntax, and convert between JSON, CSV, YAML, and XML — all instantly in your browser.

Client-Side Only

All processing runs in your browser — your data is never sent to a server or stored

No Data in URLs

Your input text is never written to the URL — safe to paste sensitive data

Common JSON Syntax Errors

The 5 most frequent mistakes and how to fix them

JSON has strict syntax rules. Unlike JavaScript objects, JSON does not allow trailing commas, single quotes, comments, or unquoted keys. Use the Validate mode to catch these issues instantly.

Mistake	Fix
Trailing comma after last item	Remove the comma after the last element in arrays and objects
Single quotes instead of double	JSON requires double quotes for all strings and keys
Unquoted property names	All object keys must be wrapped in double quotes
Comments in JSON	JSON does not support comments — remove // and /* */ blocks
Missing commas between items	Each key-value pair or array item needs a comma separator

JSON vs XML vs YAML vs CSV

When to use each data format

Each data format has strengths. JSON dominates web APIs, YAML is preferred for configuration files, XML remains standard for enterprise SOAP services, and CSV is ideal for tabular data and spreadsheets.

Format	Best For	Readability	Size
JSON	APIs, config files, web apps	Medium	Small
XML	SOAP APIs, documents, SVG	Low	Large
YAML	Config files, CI/CD, K8s	High	Small
CSV	Spreadsheets, tabular data	High	Smallest

Practical Use Cases

Real-world scenarios where JSON conversion saves time

API Development

Format API responses for debugging, validate request payloads, and convert between JSON and XML for SOAP integrations

Data Migration

Convert CSV exports from databases or spreadsheets into JSON for web apps, or JSON API data into CSV for analysis

DevOps & Config

Convert JSON configs to YAML for Kubernetes, Docker Compose, and CI/CD pipelines like GitHub Actions

Data Exchange

Transform data between JSON, XML, CSV, and YAML for system integrations and ETL pipelines

Frequently Asked Questions

Common questions and detailed answers

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Last updated Mar 28, 2026