Can I select a CSV file?

Yes. Select a CSV, TSV, or text file up to 5 MB. The file is read locally, not uploaded.

Which delimiters are supported?

Choose comma, semicolon, or tab to match the file. Delimiters inside quoted fields remain part of the cell.

Are quoted multiline cells supported?

Yes. Quoted fields may contain line breaks and doubled quotes. Unclosed quotes and unexpected characters are reported as errors.

Will numbers or booleans be converted automatically?

Not by default. Enable type detection to convert supported values; leave it off to preserve cell text and leading zeroes.

Why are duplicate headers or uneven rows rejected?

Duplicate names would overwrite properties, and extra or missing fields could lose data. Fix the header or field count, or select the correct delimiter.

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CSV to JSON

Parse CSV data into structured JSON arrays and objects for quick app, API, and spreadsheet workflows.

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CSV to JSON

Values stay strings unless type detection is on, including spaces and quoted multiline cells. By default the first row must have unique, non-empty headers and every data row must match its field count; tolerant mode renames duplicate headers and pads or truncates ragged rows with a warning instead of failing. Files up to 5 MB are read locally, not uploaded.

CSV file

DelimiterOutput format

First row is the header Detect numbers & booleans Tolerate duplicate headers & ragged rows

Type detection converts values like 42 and true, but keeps leading-zero values like 007 and long IDs as strings.

How to use it

Paste delimited text or select a local CSV/TSV file.
Choose comma, semicolon, or tab to match the data.
Select Convert CSV to JSON; resolve duplicate headers or row-width errors before copying.

What is CSV to JSON?

Parse CSV data into structured JSON arrays and objects for quick app, API, and spreadsheet workflows.

How it works

Paste CSV or select a local file up to 5 MB. Detect or choose the delimiter and header handling. A quote-aware parser preserves spaces, escaped quotes, and multiline cells. Values stay strings unless type detection is enabled.

Example input and expected output

Input

name,note
alpha,"a,b"

Expected output

[{"name":"alpha","note":"a,b"}]

Common uses

Convert a spreadsheet export while keeping leading zeroes as strings.
Read quoted multiline cells without splitting them into separate records.

Limitations

Values stay strings by default; optional type detection can convert numbers and booleans.
Pasted text is limited to 5,000,000 characters and file selection to 5 MB. With a header row enabled, headers must be unique and non-empty.

Frequently asked questions

Can I select a CSV file?: Yes. Select a CSV, TSV, or text file up to 5 MB. The file is read locally, not uploaded.
Which delimiters are supported?: Choose comma, semicolon, or tab to match the file. Delimiters inside quoted fields remain part of the cell.
Are quoted multiline cells supported?: Yes. Quoted fields may contain line breaks and doubled quotes. Unclosed quotes and unexpected characters are reported as errors.
Will numbers or booleans be converted automatically?: Not by default. Enable type detection to convert supported values; leave it off to preserve cell text and leading zeroes.
Why are duplicate headers or uneven rows rejected?: Duplicate names would overwrite properties, and extra or missing fields could lose data. Fix the header or field count, or select the correct delimiter.