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JSON Formatter & Validator

Beautify, minify, validate, auto-fix, schema-correct — and convert JSON to TypeScript, CSV, YAML or XML. 100% in your browser, nothing sent to any server.

🔒 100% Private — runs in your browser ⚡ Instant — no upload, no wait 🌟 Free forever — no signup, no ads
Auto-fix Report
JSON Schema

Paste your JSON Schema and click Fix with Schema — the tool will coerce each value to the correct type automatically.

✓ Auto-fixed (unambiguous)
Wrong types — "25"25
String to boolean — "yes"true
Number to string — 1042"1042"
Unquoted identifiers → strings
Version strings — 2.1.0"2.1.0"
⚠ Flagged only (needs your decision)
enum — wrong value, can't guess which is correct
minimum/maximum — out of range, your intent unclear
minLength/maxLength — can't rewrite your string
pattern — can't construct a valid value
additionalProperties — unknown keys flagged
required — missing fields flagged
Input JSON
Output
Bookmark this tool (Ctrl+D) — free forever, no account needed

5 buttons, each for a different task

Beautify

Paste any valid JSON and click to get clean, properly indented output with syntax highlighting. Use the indent selector (2 or 4 spaces) before clicking.

Minify

Strips all whitespace and indentation. Use before sending JSON to an API or saving to a database to reduce payload size.

Validate

Checks if your JSON is syntactically correct without modifying it. Shows a green tick if valid — or a red error with the exact line and column if not.

Fix & Analyze

Automatically repairs trailing commas, single quotes, missing commas, unquoted keys, Python literals (True/False/None). Then runs data analysis.

Schema Fix
Most powerful feature

When your JSON has the right structure but wrong types, Schema Fix reads your JSON Schema and corrects every value automatically.

Step 1
Click Schema Fix — panel opens
Step 2
Paste schema or click Load sample
Step 3
Click Fix with Schema — done
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FAQ

Frequently Asked Questions

Everything you need to know about formatting and validating JSON online.

What is a JSON formatter? +

A JSON formatter takes raw or minified JSON and reformats it with proper indentation and line breaks, making it easy to read and debug. It also validates the JSON structure and highlights syntax errors.

Is my JSON data safe to paste here? +

Yes, completely. GetPDFMint's JSON formatter is 100% client-side. Your data never leaves your browser and is never sent to any server. You can safely paste API keys, config files, and sensitive data.

What is the difference between format and minify? +

Formatting adds indentation and line breaks to make JSON human-readable. Minifying removes all whitespace to reduce file size — useful for production APIs and config files where bandwidth matters.

What JSON errors does this tool detect? +

Common errors detected include trailing commas, missing quotes around keys, single quotes instead of double quotes, mismatched brackets, and invalid data types. The tool pinpoints the exact line and character of each error.

Can I format large JSON files? +

Yes. Since all processing happens in your browser, there are no server upload limits or timeouts. You can format large JSON files directly without any restrictions.

Does this work with nested objects and arrays? +

Yes. The formatter handles all valid JSON structures including deeply nested objects, arrays of objects, mixed types, and complex hierarchies. The tree view helps visualize nested structures at any depth.

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