Developer

JSON Formatter & Validator

Paste or load JSON, then validate syntax with JSON.parse, pretty-print with configurable indentation, or minify to a single line. Errors show line and column hints when the runtime reports a position — all processing stays in your browser.

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Drop a .json file here or click to browse — contents are read only on your device
Output 
Output appears here after Format, Minify, or Validate.
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What is JSON?

JSON (JavaScript Object Notation) is a lightweight text format for structured data: objects as { } maps of string keys to values, arrays as [ ] lists, and literals for strings, numbers, booleans, and null. It is the lingua franca of REST APIs, mobile app backends, configuration files, and browser fetch responses. Unlike XML, JSON has a single root value and strict quoting rules — which is why a dedicated formatter saves time when logs or API payloads arrive minified on one line.

What this tool does

DroidXP’s JSON Formatter runs JSON.parse in your browser to check that text is valid JSON, then JSON.stringify to produce either indented (pretty) or compact (minified) output. When parsing fails, engines such as V8 usually include a position in the error message; we translate that into a line and column and show the matching source line when possible. Optional sorted keys help compare diffs across exports where key order would otherwise vary.

  • Format: Pretty-print with 2 spaces, 4 spaces, or tabs.
  • Minify: Remove insignificant whitespace for production payloads.
  • Validate only: Confirm syntax without rewriting the input text.
  • Privacy: No upload — your JSON never leaves this tab unless you copy it out.

How to use this tool

  1. Step 1: Paste JSON into the input area, or drag a .json file onto the drop zone.
  2. Step 2: Choose indentation for pretty output (or leave defaults).
  3. Step 3: Click Format to beautify, Minify for a single line, or Validate only to check syntax.
  4. Step 4: Use Copy output to paste into editors, tickets, or API clients.

Syntax vs schema

This page validates JSON syntax only (balanced braces, valid strings, no trailing commas). It does not enforce a JSON Schema, business rules, or API contracts. For schema validation, use a dedicated library or service in your pipeline.

Frequently Asked Questions

Does DroidXP upload my JSON?

No. Parsing and formatting run entirely in your browser. For regulated data, still follow your organization’s policy on pasting secrets into any web page — including local-only tools.

Why does the validator reject trailing commas?

Standard JSON (ECMA-404 / RFC 8259) does not allow trailing commas after the last array element or object property. Some tools accept JSON5-style commas, but JSON.parse follows strict JSON — remove trailing commas to pass validation.

Does formatting or minifying change my data?

Whitespace is normalized. For normal data, values are preserved. Very large integers may lose precision because JavaScript numbers are IEEE-754 doubles — the same limitation as parsing JSON in Node or the browser elsewhere.

What does “Sort object keys” do?

It recursively sorts keys alphabetically on objects before stringify. Arrays keep their order. Use it for stable diffs; skip it if key order is meaningful for your application.

Can I format very large JSON files?

Large documents can slow down or exhaust memory in the tab. For multi‑megabyte logs, prefer desktop tools or stream parsers. This page is best for typical API payloads and config snippets.

Why doesn’t my error show a line number?

Line and column hints depend on the browser’s error message including a position. If the engine omits it, you still get the raw message — check for stray commas, unescaped quotes, or truncated copy/paste.

Is this a replacement for jq or server-side formatters?

It is a quick, private formatter for ad hoc use. For shell pipelines, CI, or huge files, keep using jq, fx, or your language’s native JSON tooling.

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