Converting between CSV and JSON, correctly
CSV looks trivial until real data arrives: fields containing commas, quotes or line breaks must be wrapped in quotes and escaped by doubling ("") per RFC 4180 — a naive split(',') destroys such files. This converter implements a proper state-machine parser, so "Turing, Alan" stays one field. In CSV → JSON mode your header row becomes object keys and each row an object — the array-of-objects shape REST APIs and databases expect. Optional type conversion turns 42, true and empty cells into native numbers, booleans and null (switch it off to protect ZIP codes and IDs with leading zeros).
JSON → CSV accepts an array of objects, unions all keys into columns, serializes nested structures as JSON strings and escapes output correctly for Excel and Google Sheets. Delimiter auto-detection handles the semicolon-separated CSVs that European Excel locales export, plus TSV. Everything runs locally — safe for customer data. Validate tricky JSON first in the JSON Formatter, or compare two exports with the Text Diff Checker.