What happens if two columns have the same header?

The second gets a numbered suffix — `email` and `email_2`. Writing both to the same key would silently drop one column's data, and the row would look complete while being wrong. An ugly key is much easier to notice than a missing one.

What if my CSV has no header row?

Turn off the header toggle and the columns are named `column_1`, `column_2` and so on, with the first row treated as data. That is usually what you want for an export that omitted its header.

Is my data uploaded to convert it?

No. The parsing and conversion happen in this page. That matters here more than most places, because a CSV people need converting is usually an export of real records — customers, orders, payroll.

CSV to JSON Converter

Convert a CSV into a JSON array of objects, one object per row, keyed by the header. Quoted fields are parsed to the spec, so commas and line breaks inside a value survive. Numbers and booleans become real JSON types — except where doing so would destroy the data, which is why `007` stays a string and a nineteen-digit ID doesn't get silently rounded.

Your text

Delimiter

First row is a header

Convert numbers and booleans

Leading zeros and very long digit strings stay as text, because those are identifiers rather than numbers.

Indent the output

Result

Nothing is uploaded — this tool runs inside your browser, so your files never leave your device.

Help us improve

Why use this tool

One JSON object per row, keyed by the header names
Detects the delimiter, and handles quoted commas and line breaks
Converts numbers and booleans, but leaves identifiers alone
Numbers duplicate headers instead of silently overwriting a column

How it works

1Paste your CSV.
2Turn type conversion off if you want every value kept as a string.
3Copy the JSON out, or download it.

CSV to JSON Converter — frequently asked questions

Because a leading zero means the digits are an identifier, not a quantity — a part number, a phone extension, a US zip code. Converting it to 7 destroys it, and nothing downstream can put the zeros back. Anything too long to be a safe JavaScript integer is left as a string for the same reason: a 19-digit database ID loses its last two digits the moment it becomes a number.

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