JSON Validator
Validate JSON syntax and pinpoint errors instantly in your browser.
JSON Input
Valid JSON
31 lines · 521 bytes · Depth 5
- Local ProcessingYour JSON is validated entirely in your browser memory. Payloads never touch remote servers.
- Precise Error LocationFind syntax errors by line, column, and character offset with a visual caret pointer.
- Standards-Based ValidationStrict compliance with RFC 8259 and ECMA-404 specifications for reliable downstream consumption.
Educational Reference
Understanding Common JSON Syntax Errors
JSON is strict about commas, quotes, and escaping. Here are the most frequent syntax pitfalls and their valid alternatives.
Trailing Commas
JSON prohibits commas after the last property in an object or element in an array.
{
"name": "Alice",
}{
"name": "Alice"
}Single Quotes
JSON strings and object property keys must always be enclosed in double quotes ("), never single quotes (').
{ 'name': 'Alice' }{ "name": "Alice" }Unquoted Object Keys
Unlike JavaScript object literals, all property names in standard JSON must be quoted strings.
{ name: "Alice" }{ "name": "Alice" }Unescaped Backslashes
Backslashes inside string values (like Windows file paths) must be escaped as double backslashes (\\).
{
"path": "C:\temp"
}{
"path": "C:\\temp"
}Need a step-by-step walkthrough to diagnose and resolve tricky syntax errors?
Developer Validation Guides
How to validate JSON syntax in popular backend runtimes and programming languages.
// Native JavaScript / Node.js
function isValidJson(input) {
try {
JSON.parse(input);
return true;
} catch (error) {
return false;
}
}
const valid = isValidJson('{"name": "Alice"}');
console.log("Valid:", valid);Knowledge Base