JSON•100% Client-Side

JSON Validator & Linter

Verify the syntax of your JSON documents. Find missing keys, commas, or mismatched brackets in real-time, complete with exact line-number error highlights. Privacy-first, local client-side linting.Reference Spec: IETF RFC 8259 (JSON Data Interchange Format Specification)→

JSON Input to Validate

Validation Report

Waiting for input...

Paste or write JSON to view its validation report.

Try with Examples

Frequently Asked Questions (JSON Validator)

What makes JSON invalid?

Common mistakes that invalidate JSON include: using single quotes instead of double quotes for strings/keys, unquoted keys, trailing commas at the end of lists/objects, missing commas between elements, and mismatched curly braces or square brackets.

How does the validator calculate JSON depth?

Depth is determined by counting the maximum nesting level of objects or arrays. For example, a flat object has a depth of 1, whereas { 'a': { 'b': 2 } } has a depth of 2.

What is the difference between JSON formatting and JSON validation?

JSON formatting cleans up whitespace and indents code to make it readable. JSON validation strictly checks if the code follows JavaScript Object Notation syntax rules and locates syntax issues.

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