How It Works Under the Hood
Parses JSON synchronously in browser memory using native JavaScript JSON parsing and highlights syntax errors with exact line and column coordinates. Auto-repair uses a lexer pass to fix unquoted keys, comments, and trailing commas without altering string contents.
Step-by-Step Instructions
Paste raw JSON or upload a .json file.
Click "Format (2 Spaces)" or "Format (4 Spaces)" to beautify.
If syntax errors exist, review the highlighted line pointer or click "Auto-Repair Syntax".
Switch to "Tree Inspector" to browse nested arrays and objects interactively.
Key Features & Performance
- Lexer-Safe Auto-Repair: Preserves string literals like "keep,}" and URLs intact
- Error Line Pointers: Pinpoints exact line and column of invalid syntax
- Dual View: Toggle between code editor and interactive collapsible tree
- One-Click Minify: Strip whitespace for production payloads
Local Browser Processing & Privacy
Traditional web converters upload your documents, snippets, or media files to remote servers. JSON Formatter, Validator & Diff runs inside your browser tab:
Your input text and files are processed locally without uploading payloads to a processing server.
Microdeck does not log or store the files or inputs you paste into tool workspaces (normal static hosting/CDN requests still load page assets).
Working outputs stay in your browser tab and are released when you reset the tool or close the tab.
Frequently Asked Questions
How large of a JSON file can I format?
Processing runs in browser memory using native JSON parsing. Typical API payloads and multi-megabyte JSON files format quickly, while very large files (15 MB+) depend on available browser RAM.
Does this tool upload my proprietary JSON data?
Never. All parsing and formatting occurs strictly in your browser RAM.
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