JSON Strict Validator (RFC 8259, Number Precision)

Validate JSON against the strictest interpretation of RFC 8259 — the official JSON spec. Catches: trailing commas, comments, single quotes, unquoted keys, NaN / Infinity, and numbers that exceed JavaScript's safe integer range (which silently corrupt during parse).

How to use the JSON Strict Validator (RFC 8259, Number Precision)

Paste JSON. The validator checks each kind of non-strict construct and reports per-line where each violates the spec. Useful when preparing JSON for a strict consumer (a wire protocol, a database column with strict JSON validation, a federated standard).