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CSV ↔ JSON converter
Convert flat CSV and JSON records while keeping control of the data.
CSV cells become JSON strings, keeping IDs such as 001 intact.
Your result
Flat records, clear rules.
CSV → JSON creates one object per record and keeps every cell as a string. JSON → CSV accepts a nonempty array of flat objects; numbers keep their original literal spelling, and booleans become true or false. Nested objects and arrays are rejected.
Missing properties and JSON null both become empty CSV cells, so that distinction cannot survive a CSV round trip. Within each JSON object, integer-like property names come first in numeric order; other names keep their order of appearance. New columns are appended as later records introduce them. Duplicate JSON property names are rejected to prevent silently dropping values. JSON and CSV are data formats, not executable code.
CSV headers are trimmed and must be unique. Records are limited to 20,000 and columns to 100; CSV headers can have up to 200 characters. Formula-safe CSV output can prefix affected cells; spreadsheet apps can still apply their own type conversion.
Empty physical lines are skipped; explicitly empty CSV records are retained. Record numbers refer to data records after skipped lines.