JSON ↔ CSV

Convert CSV and JSON either way with delimiter auto-detect, a sortable table preview, error reporting, file load and download — all in your browser.

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Delimiter
JSON indent
CSV
JSON

Convert between CSV and JSON either way, with delimiter auto-detect (comma, tab, semicolon, pipe), a sortable table preview of the parsed rows, parse warnings with row numbers, and one-click file load or download. Everything runs in your browser, so spreadsheets with customer data never leave your device.

How to use JSON ↔ CSV

  1. 1Pick a direction (CSV → JSON or JSON → CSV), or load a .csv / .json file.
  2. 2Adjust delimiter, header, type-casting, and trimming as needed.
  3. 3See the converted output side-by-side, with a live table preview below.
  4. 4Copy the result or download a .csv / .json file.

Delimiters and headers — the things that usually break

European spreadsheets use semicolons. Excel sometimes exports tab-separated. A pipe is common in legacy systems. Auto-detect picks the right one almost every time, and you can override it if you’re sure. The delimiter Primova actually used is shown on the input so there’s no ambiguity.

Not every CSV has a header row. Toggle “First row is a header” off and Primova outputs rows as arrays with generic col1, col2 keys — useful for log dumps and raw data.

Preview your data as a real table

Validating a conversion by reading raw CSV or pretty-printed JSON is slow. Primova renders the parsed rows in a sticky-header table below the editors so you can spot the shifted column, the stray quote, or the type that wasn’t cast as a number. Up to 50 rows are previewed at once.

Type casting is optional — leave it off when you have IDs or zip codes like 01234 that must stay strings; turn it on for clean numeric/boolean data.

Frequently asked questions

No. Parsing, conversion, the table preview, and the download all happen in your browser, so even spreadsheets with personal data never leave your device.
Comma, tab (TSV), semicolon, and pipe — plus an auto-detect mode that picks the right one from the first lines of your file. The delimiter Primova ended up using is shown beneath the input.
Turn off “First row is a header” and the rows are output as arrays with generic keys (col1, col2, …). Switch back to JSON → CSV to round-trip cleanly.
Yes — disable “Type values”. With type casting off, every field is kept as a string so leading zeros, ISBNs, and large IDs aren’t silently turned into numbers.
Yes. Anything malformed (mismatched quotes, ragged rows, etc.) appears in a warnings list with the row number, so you can jump straight to the bad line.
Yes — free with no sign-up and no limit on file size beyond what your device can hold in memory.

Still have questions?

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