JSON Formatter & Validator
Format, beautify, minify, and validate JSON — with exact error locations
Methodology & standardsRuns on your device
Inputs
Results update liveInterpretation
How JSON Formatting works
The formatter parses your JSON, reports the exact line and column of any syntax error, and re-serializes it with your chosen indentation — or minified. Everything runs locally in your browser.
Example
Worked example
A realistic scenario showing how the calculation guides a practical decision.
Worked example
input{"b":2,"a":[1, 3,]}
operationJSON.parse → trailing comma after 3
resulterror on line 1, column 18 — the ']' right after the stray comma
What it means: Deleting the stray comma just before the highlighted bracket makes the document parse; Format then re-prints it with stable 2-space indentation and insertion key order.
Watch out
Common mistakes
- JSON (JavaScript Object Notation) is a lightweight data interchange format. Keys must be double-quoted strings, and values can be strings, numbers, booleans, null, arrays, or objects. Trailing commas are not allowed.
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