JSON ToolNative JSON

JSON Formatter / Validator

Free JSON Formatter & Validator - Format, validate, and beautify JSON data with syntax highlighting. No login, no sign in, no registration required. Perfect for developers working with APIs, configuration files, and data validation.

← Browse JSON Tools

Paste your JSON

We validate everything locally in your browser. Paste payloads, configs, or logs.

JSON input

181 characters500,000 max

We formatted the output in the preview pane automatically.

Formatter controls

Pick your indentation style, then format, minify, or export the clean JSON.

Indentation style

Download JSON

Valid JSONJSON is valid

We formatted the output in the preview pane automatically.

Valid JSON

Ready to copy, download, or minify for production use.

Readable preview

Indentation updates instantly so you can scan nested data.

Output preview

Switch between formatted and minified views. Copy or download once everything looks right.

{
  "name": "FreeToolbox",
  "url": "https://itoolbox.dev",
  "features": [
    "Format JSON instantly",
    "Validate syntax as you type",
    "Copy or download clean output"
  ]
}

Format and validate JSON in minutes

Clean up payloads, inspect nested objects, and hand off perfect JSON without leaving your browser.

Paste or drop your JSON payload

Bring responses from APIs, config files, or logs. We keep everything in your browser.

Supports large payloads with instant syntax detection.
Whitespace, tabs, and trailing commas are handled gracefully.

Validate structure automatically

We parse your input in real time and surface precise error positions if something breaks.

Line and column numbers help you jump to issues quickly.
Error snippets highlight the exact region that needs attention.

Format or minify in a click

Pretty-print with 2 or 4 spaces, switch to tabs, or compress everything for transport.

Preview updates instantly when indentation changes.
Minified JSON is perfect for network requests or environment variables.

Share clean output confidently

Copy to clipboard, download as a .json file, or hand off minified payloads to teammates.

Download files keep UTF-8 encoding and original ordering.
Copy buttons include both formatted and minified versions.

Where teams rely on clean JSON

Ship integrations faster by catching issues before they reach production.

API debugging & integrations

Normalize responses from REST or GraphQL services before committing to docs or tests.

Spot malformed payloads before they land in staging.
Generate reproducible examples for bug reports and support tickets.
Share formatted responses directly in PRs or Slack threads.

Configuration management

Keep JSON-based environment files, CMS exports, or feature flags consistent across teams.

Verify that new keys maintain valid structure before deploying.
Minify config for production while keeping readable drafts locally.
Catch typos before they break build pipelines or CLI tools.

Data pipelines & QA

Validate samples flowing between services, data warehouses, or analytics dashboards.

Inspect nested data without losing track of indentation.
Confirm payload shape matches contracts and schemas.
Download sanitized subsets to share with stakeholders securely.

JSON handoff best practices

Make documentation, reviews, and deployments smoother by keeping payloads tight and consistent.

Easier reviews, fewer surprises

Follow these quick guidelines to keep JSON readable in diffs and reliable in production.

Keep a version-controlled library of sample JSON payloads for regression testing.
Use consistent indentation (2 or 4 spaces) across repos to avoid noisy diffs.
Strip comments before shipping to production—JSON does not officially support them.
Validate against a JSON Schema when working with mission-critical integrations.
Minify before deploying to save bytes in client-side bundles or configuration files.

JSON formatter FAQs

Get answers about limits, privacy, and the formatter's capabilities.

Does formatting happen locally?

Yes. Everything runs in your browser with the native JSON parser—no data leaves your device.

How big of a JSON file can I format?

We comfortably handle payloads up to a few hundred kilobytes. For multi-megabyte files, we suggest using Node.js tooling.

Can I change indentation levels?

Absolutely. Toggle between 2 spaces, 4 spaces, or tabs. The preview updates instantly.

Do you support JSON5 or comments?

We currently focus on strict JSON. Remove comments or trailing commas before validating.

Can I download the formatted result?

Yes. Use the download action to save a UTF-8 JSON file. We keep your indentation preferences intact.

Related Tools

JSON Path Finder & Diff

Free JSON Path Finder & Diff Tool - Find property paths in JSON objects and compare differences between JSON files.

JSON ToolNative JSON

JSON Formatter / Validator

← Browse JSON Tools

Paste your JSON

We validate everything locally in your browser. Paste payloads, configs, or logs.

JSON input

181 characters500,000 max

We formatted the output in the preview pane automatically.

Formatter controls

Pick your indentation style, then format, minify, or export the clean JSON.

Indentation style

Download JSON

Valid JSONJSON is valid

We formatted the output in the preview pane automatically.

Valid JSON

Ready to copy, download, or minify for production use.

Readable preview

Indentation updates instantly so you can scan nested data.

Output preview

Switch between formatted and minified views. Copy or download once everything looks right.

{
  "name": "FreeToolbox",
  "url": "https://itoolbox.dev",
  "features": [
    "Format JSON instantly",
    "Validate syntax as you type",
    "Copy or download clean output"
  ]
}

Format and validate JSON in minutes

Clean up payloads, inspect nested objects, and hand off perfect JSON without leaving your browser.

Paste or drop your JSON payload

Bring responses from APIs, config files, or logs. We keep everything in your browser.

Supports large payloads with instant syntax detection.
Whitespace, tabs, and trailing commas are handled gracefully.

Validate structure automatically

We parse your input in real time and surface precise error positions if something breaks.

Line and column numbers help you jump to issues quickly.
Error snippets highlight the exact region that needs attention.

Format or minify in a click

Pretty-print with 2 or 4 spaces, switch to tabs, or compress everything for transport.

Preview updates instantly when indentation changes.
Minified JSON is perfect for network requests or environment variables.

Share clean output confidently

Copy to clipboard, download as a .json file, or hand off minified payloads to teammates.

Download files keep UTF-8 encoding and original ordering.
Copy buttons include both formatted and minified versions.

Where teams rely on clean JSON

Ship integrations faster by catching issues before they reach production.

API debugging & integrations

Normalize responses from REST or GraphQL services before committing to docs or tests.

Spot malformed payloads before they land in staging.
Generate reproducible examples for bug reports and support tickets.
Share formatted responses directly in PRs or Slack threads.

Configuration management

Keep JSON-based environment files, CMS exports, or feature flags consistent across teams.

Verify that new keys maintain valid structure before deploying.
Minify config for production while keeping readable drafts locally.
Catch typos before they break build pipelines or CLI tools.

Data pipelines & QA

Validate samples flowing between services, data warehouses, or analytics dashboards.

Inspect nested data without losing track of indentation.
Confirm payload shape matches contracts and schemas.
Download sanitized subsets to share with stakeholders securely.

JSON handoff best practices

Make documentation, reviews, and deployments smoother by keeping payloads tight and consistent.

Easier reviews, fewer surprises

Follow these quick guidelines to keep JSON readable in diffs and reliable in production.

Keep a version-controlled library of sample JSON payloads for regression testing.
Use consistent indentation (2 or 4 spaces) across repos to avoid noisy diffs.
Strip comments before shipping to production—JSON does not officially support them.
Validate against a JSON Schema when working with mission-critical integrations.
Minify before deploying to save bytes in client-side bundles or configuration files.

JSON formatter FAQs

Get answers about limits, privacy, and the formatter's capabilities.

Does formatting happen locally?

Yes. Everything runs in your browser with the native JSON parser—no data leaves your device.

How big of a JSON file can I format?

We comfortably handle payloads up to a few hundred kilobytes. For multi-megabyte files, we suggest using Node.js tooling.

Can I change indentation levels?

Absolutely. Toggle between 2 spaces, 4 spaces, or tabs. The preview updates instantly.

Do you support JSON5 or comments?

We currently focus on strict JSON. Remove comments or trailing commas before validating.

Can I download the formatted result?

Yes. Use the download action to save a UTF-8 JSON file. We keep your indentation preferences intact.

Related Tools

JSON Path Finder & Diff

Free JSON Path Finder & Diff Tool - Find property paths in JSON objects and compare differences between JSON files.