Most JSON errors are silly - a missing comma, an unquoted key, a stray trailing comma. The validator parses your JSON live as you type and points to the exact line and column of the first error. Auto-repair fixes the common ones (trailing commas, single quotes, unquoted keys) so you can get back to work.
When to use this
Use when: an API client returns 'Invalid JSON' and you need to find the typo, debugging a config file that won't parse, sanitizing JSON pasted from logs, validating webhook payloads before forwarding them downstream.
Frequently Asked Questions
What does the validator check?
Standard JSON spec (RFC 8259): correct types, balanced brackets/braces, properly quoted keys and strings, valid number formats, no trailing commas. Auto-repair handles common non-standard inputs but the strict validator flags them as errors first.
Can it find duplicate keys?
Yes - the validator warns on duplicate keys at the same level (technically valid JSON but usually a bug). The tree view shows you exactly which keys repeat.
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