JavaScript Object to JSON

How It Works

Paste a JavaScript object literal and instantly get valid JSON output. The tool parses relaxed JS syntax that JSON.parse() would reject — single quotes, trailing commas, unquoted keys, comments, and more — and converts it to strict JSON.

Features

• Single quotes: 'hello' becomes "hello"
• Unquoted keys: { name: "val" } becomes { "name": "val" }
• Trailing commas: safely stripped from objects and arrays
• Comments: // single-line and /* */ multi-line comments removed
• undefined/NaN/Infinity: converted to null with warnings
• Template literals: backtick strings converted to regular strings
• Hex/Octal/Binary: 0xFF, 0o77, 0b1010 converted to decimal
• Nested structures: handles deeply nested objects and arrays
• Warnings: shows what was converted (undefined, NaN, template literals)
• 5 examples: single quotes, trailing commas, unquoted keys, comments, mixed
• Private: runs entirely in the browser — no data transmitted

Use Cases

• Fixing “Unexpected token” errors when pasting JS objects into JSON fields
• Converting config objects from JS files to JSON format
• Cleaning up console.log output to valid JSON
• Converting JavaScript test fixtures to JSON data files
• Quick formatting of hand-written JS-style data structures