JSON-Formatter

JSON-Code formatieren, validieren und komprimieren.

Format & Beautify JSON

Formatiertes JSON ist lesbar und hilft beim Debuggen von Strukturfehlern. APIs geben oft schwer lesbares komprimiertes JSON zurück – dieses Tool löst das sofort.

Datenschutz zuerst

Ihre JSON-Daten verlassen niemals Ihren Browser. Die gesamte Formatierung und Validierung erfolgt lokal mit JavaScript, sodass Ihre Daten privat und sicher bleiben.

Reading Messy JSON: Why Formatting Matters

Overview

JSON has become the universal data format of the web — APIs, config files, NoSQL databases, logs, and almost every modern application speak it. But minified JSON (no whitespace, single line) is unreadable by humans. Pretty-printing JSON adds indentation and line breaks to reveal nesting structure, making bugs and missing fields immediately visible. This tool not only formats, but also validates (catches missing brackets, trailing commas, unquoted keys), minifies for production, and converts between JSON and related formats.

How It Works

JSON.parse() parses input; JSON.stringify(parsed, null, 2) reformats with 2-space indentation. Errors from JSON.parse provide a position so the tool can highlight where the syntax broke. The validator catches the common JSON5 mistakes — trailing commas after the last array/object element, single quotes instead of double, unquoted object keys, and JS-style comments (which are not part of strict JSON). Minify removes all unnecessary whitespace, useful when shipping JSON in URLs or compact storage.

When to Use This

Debugging API responses copied from a terminal. Cleaning up config files written by hand. Reviewing third-party API documentation samples. Validating JSON Schema example data. Inspecting Webpack/Vite build manifests. Comparing two JSON files (after formatting both, a diff is meaningful). Preparing JSON for inclusion in code (escaped quotes, etc.).

Frequently Asked Questions

What's the difference between JSON and JSON5?

JSON (RFC 8259) is strict: double-quoted keys/strings, no trailing commas, no comments. JSON5 extends this with JavaScript-like syntax (single quotes, unquoted keys, comments, trailing commas). This tool warns when input is JSON5-style invalid JSON.

Can this tool handle huge files?

Up to ~50 MB in modern browsers before performance suffers. For 100MB+ files, use a streaming parser like jq (CLI) or stream-json (Node).

How is JSON different from YAML?

JSON is a strict subset of JavaScript object syntax; YAML is a human-friendly format that supports comments, anchors, and looser syntax. JSON is faster to parse and unambiguous; YAML is easier to write by hand. The tool can convert between the two.