Beautify and validate JSON, convert between JSON, YAML, and CSV, and format SQL. Errors are reported with line and column.
Large integer IDs in JSON lose digits in JavaScript because numbers are IEEE 754 doubles, exact only up to 2^53 − 1. Keep them exact with string IDs or BigInt.
Trailing commas, single quotes, unquoted keys, comments, unclosed brackets, NaN and duplicate keys: why each one breaks JSON under RFC 8259 and how to fix it.
To open JSON in Excel, convert it to CSV with a UTF-8 BOM and RFC 4180 quoting. See how commas, quotes, line breaks and leading zeros are handled.