JSON Validator

Paste or upload JSON to validate syntax, pinpoint parse errors, and format valid JSON without sending data to a server.

What this JSON formatter does

This is a complete JSON toolkit that runs entirely in your browser. Whether you are cleaning up a minified API response, hunting down a stray comma that breaks a config file, or inspecting a deeply nested payload, everything happens locally — nothing is uploaded, logged, or stored on a server.

• Format & beautify — add clean 2-space, 4-space, or tab indentation so JSON is readable.
• Minify — strip whitespace to shrink payloads for production and faster transfers.
• Validate — catch syntax errors in real time with exact line and column hints.
• Tree view — explore nested objects and arrays, then click any node to copy its path.
• Convert — export to CSV, YAML, or XML in one click.
• Compare — diff two JSON objects side by side with color-coded changes.

Format vs. minify: what is the difference?

Formatting (also called beautifying or prettifying) adds indentation and line breaks so a human can scan the structure quickly — ideal while you are debugging or reviewing data. Minifying does the opposite: it removes every optional space and newline to make the file as small as possible, which is what you want when shipping JSON over the network or embedding it in code. Either way the underlying data is identical — only the presentation changes. New to this? Read our deep dive on how to minify JSON.

Common use cases

• Debugging API responses — paste a raw REST or GraphQL response and instantly read it as indented, color-coded JSON. See our guide to debugging APIs with JSON.
• Fixing broken config files — package.json, tsconfig.json, and CI manifests fail silently on a trailing comma; the validator points to the exact spot. See common JSON errors.
• Inspecting nested data — collapse and expand large structures in tree view instead of scrolling through thousands of lines.
• Preparing data for code — minify before pasting JSON into a script, or copy a single value's path to use in your app.

Latest Articles

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Common JSON Errors and How to Fix Them

Identify and fix the most common JSON errors: trailing commas, single quotes, unquoted keys, and more. Debug your JSON fast.

Debug REST APIs with JSON Formatting

Learn to debug REST APIs faster with JSON formatting and validation tools. Practical techniques for reading responses and fixing common API issues.

How to Minify JSON (and When to Beautify Instead)

Learn how to minify JSON to shrink payloads, why it speeds up APIs, and when to beautify instead. Includes browser, JavaScript, Python, and jq examples.