JSON Validator: Find Syntax Errors Fast
Online JSON validator: paste content to check it against JSON syntax and locate common errors like trailing commas, missing quotes, or mismatched brackets.
JSON is strict: keys must be double-quoted, strings cannot use single quotes, no trailing comma is allowed after the last element, and booleans / null must be lowercase. Any deviation causes a parse failure.
A validator scans the whole text, finds the illegal position, and tells you what is wrong — helping you quickly turn "almost-valid JSON" into usable data before formatting or sending it to an API.
Common mistakes include: single quotes around keys or values, a trailing comma after the last array/object item, Chinese quotation marks slipping into a string, and comments inside standard JSON (which does not allow them).