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CSV to JSON / JSON to CSV Converter — Paste & Convert

Convert CSV to JSON objects or a JSON array back to CSV — handles quoted cells, embedded commas, newlines and semicolon/tab delimiters, entirely in your browser.

Last reviewed 2026-10-19. Rates change — verify against the official sources linked below before relying on these figures.

What this is based on

  • First CSV row is the header row; every other row becomes one JSON object keyed by header.
  • RFC-4180 quoting handled: quoted cells may contain commas, double quotes ("") and newlines.
  • JSON → CSV uses the union of all keys across objects; missing keys emit empty cells.
  • Large inputs are previewed truncated — the conversion itself always covers the full input.
  • Everything runs locally in your browser — pasted content is never uploaded, logged or stored.

Why this is a daily tool

APIs speak JSON, spreadsheets speak CSV — and every data handoff between them needs a converter. The painful cases are quoting (a cell containing a comma), multi-line cells, and semicolon-delimited European exports. This converter handles all three without mangling your data.

In the other direction, taking a JSON array from an API response into a spreadsheet for a stakeholder is exactly as common — paste the array, get headers plus rows.

Gotchas worth knowing

CSV has no types: everything is a string. '007' stays '007' here — a spreadsheet would eagerly turn it into 7. If you need typed values, convert to JSON (you can then coerce explicitly) rather than letting Excel guess.

Ragged rows (more/fewer cells than the header) are surfaced, not silently dropped — a column-count mismatch almost always means a quoting bug upstream.

Frequently asked questions

How do I convert CSV to JSON?
Paste the CSV above with headers in the first row — you get a JSON array of objects, one per data row.
Does it handle semicolons and tabs?
Yes — the delimiter is auto-detected from the first line (comma, semicolon, or tab), so European CSV exports paste straight in.
What JSON shape does JSON → CSV need?
An array of flat objects: [{"a":1},{"a":2}]. Keys become columns; nested objects serialize as JSON text inside the cell.
Is my data uploaded?
No — parsing runs fully in your browser; nothing is sent anywhere.

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