JSON_VALIDATOR_V1
JSON Validator & Linter
Goes beyond a plain prettifier — actively scans for trailing commas, single quotes, unquoted keys, stray comments, and unmatched brackets. Every issue ships with a line and column you can jump to, and most can be fixed with one click.
What does the linter check?
- Trailing commas in arrays and objects (
[1, 2,]). - Single-quoted strings — JSON requires double quotes.
- Unquoted object keys (
{ name: "Ada" }). - Comments (
//and/* */) are not part of standard JSON. - Unmatched brackets — unclosed
{or[, or stray closers.
How does auto-fix work?
The fixer walks your input character-by-character so it never touches the inside of a string. Comments are stripped, trailing commas removed, single-quoted strings re-quoted with double quotes (escaping any inner "), and bare keys wrapped in quotes. Brackets aren't auto-balanced — that needs a human eye.
When should I use AI Fix?
AI Fix routes your input through the same LLM that powers the chat assistant on this site. Reach for it when the rule-based auto-fix can't help — unbalanced brackets, ambiguous repairs, or other parse errors. The corrected JSON streams back into the editor; you can stop it mid-stream if it goes off the rails.
Related JSON tools
- JSON Diff — compare two valid JSONs side by side.
- JSON Path Finder — explore deeply nested data.
- JSON Prettier — once it's valid, format and minify.