JSON Formatter
Format, validate, and beautify JSON data with syntax highlighting
Introduction
JSON Formatter focuses on day‑to‑day developer tasks: pretty‑printing payloads, validating structure, and producing compact transport‑ready output. It’s ideal for API debugging, log inspection, and code review prep.
You get readable, stable formatting with sensible defaults, plus utilities like key sorting and minification for cleaner diffs and faster payloads. Validation highlights exact error locations for quick fixes—even with large inputs.
Key features
- Format JSON
- Validate syntax
- Syntax highlighting
- Minify JSON
How it works
Paste or drop JSON into the editor. Formatting and validation run locally in your browser for speed and privacy. Utilities like Sort Keys or Minify apply deterministic transforms, so results are predictable and CI‑friendly.
Premium features inside the app add file upload/download, large‑file handling (>5MB), and conversions (JSON ↔ CSV/YAML/XML) when you need to bridge systems.
Step-by-step usage
- Paste JSON or drop a file into the editor.
- Click Format to pretty‑print; use Validate to confirm correctness.
- Use Sort Keys for stable diffs, or Minify for transport.
- Copy the result or (premium) download a file and share.
Examples
Normalize API response for review
Paste a minified API payload and click Format for a readable structure to include in a ticket or PR.
{"name":"Ada","roles":["admin","editor"],"active":true}Minify before transport
Click Minify to remove whitespace before embedding JSON into an environment variable.
Sort keys for stable diffs
Use Sort Keys so diffs focus on value changes rather than ordering noise.
Security & privacy
Where applicable, processing runs locally in your browser. Inputs are not logged or sent to external services. Premium features inside the app use Supabase Auth to protect access. For sensitive work, prefer local files and avoid sharing secrets. Outputs include copy and download actions to minimize manual transcription errors.
Accessibility
The tool supports keyboard navigation and screen readers with ARIA labels and descriptive messages. Focus order is logical, and error messages use human‑readable language. These docs maintain proper heading hierarchy and color contrast, and the app version includes skip links and live regions where appropriate.
Limitations & disclaimers
Some advanced capabilities are available only in the DevToolsKitHub app with a premium plan. The static documentation does not execute code or store inputs. Where behaviors differ across runtimes (browsers, servers, language engines), treat outputs as representative examples.
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