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CSV to JSON Converter

CSV to JSON and back — with real quoting rules, delimiter detection, and type inference.

100% freeRuns in your browserNo signup, no watermark

Turning a spreadsheet export into JSON for an API, seed script, or config file is a daily chore — and the classic split-on-comma hack silently corrupts any file with quoted fields, embedded commas, or line breaks inside cells. This converter uses a real CSV parser that honors RFC 4180 quoting, so “Lagos, Nigeria” stays one field and a multi-line note stays one cell.

It auto-detects the delimiter (comma, semicolon, or tab — Excel exports vary by locale), can infer numbers and booleans so “42” becomes 42, and converts in both directions: paste a JSON array of objects to get a clean, correctly quoted CSV back. Files are parsed in your browser, so customer lists and financial exports are never uploaded.

How to convert CSV to JSON

  1. 1

    Paste your CSV or drop a .csv file — the delimiter is detected automatically.

  2. 2

    Toggle the header row and type inference options to match your data.

  3. 3

    Copy the JSON or download it — or switch direction to turn JSON back into CSV.

Why use Nofolo’s csv to json converter?

Real CSV parsing

Quoted fields, escaped quotes, and newlines inside cells are handled per RFC 4180 — not naive splitting.

Delimiter auto-detect

Comma, semicolon, and tab are detected from your data, with a manual override.

Type inference

Optionally convert numeric and true/false strings into real JSON numbers and booleans.

Both directions

Switch modes to turn a JSON array of objects back into a properly quoted CSV.

Header handling

Use the first row as JSON keys, or emit plain row arrays when there is no header.

Private

Parsing runs locally — spreadsheets with customer or financial data never leave your device.

Frequently asked questions

How are commas inside values handled?

Correctly. Fields wrapped in double quotes may contain commas, quotes (escaped as two double quotes), and even line breaks — the parser follows RFC 4180 rules instead of naively splitting on commas.

My CSV uses semicolons — will it work?

Yes. Semicolon-delimited files (common from Excel in many European locales) and tab-separated files are auto-detected, and you can override the delimiter manually at any time.

Can it convert JSON back to CSV?

Yes. Switch to JSON → CSV mode and paste an array of flat objects. The union of keys becomes the header row, and values containing the delimiter, quotes, or newlines are quoted properly.

Are numbers and booleans converted or left as strings?

Your choice. With type inference on, “42”, “3.14”, and “true” become real JSON numbers and booleans, while values with leading zeros (like phone numbers) stay strings. Turn it off to keep everything as strings.

Is my spreadsheet data uploaded?

No. Parsing and conversion run entirely in your browser — customer exports, financial data, and internal reports never leave your device.

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