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CSV to JSON Converter

Convert CSV to a JSON array locally.

Maintained by Roshan.

Browser-local data converter

Use CSV to JSON Converter

Quoted commas, escaped quotes, embedded line breaks, sparse rows, and UTF-8 text are parsed locally.

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About CSV to JSON Converter

CSV looks simple until a customer name contains a comma, a note spans two lines, or a quote appears inside a quoted field. Splitting every line on commas corrupts those files. This converter uses a real CSV parser and treats the first row as property names for a JSON array. It can detect comma, semicolon, tab, or pipe delimiters, remove a UTF-8 byte-order mark, preserve quoted line breaks, and report structural repairs. Values remain strings by default so postal codes and long identifiers survive. Optional type inference converts only unambiguous safe numbers, booleans, and null. Parsing and download creation happen entirely in the browser.

Work through the input

  1. Paste a table containing one header row and at least one data row. Automatic detection examines the text for a consistent delimiter. You can override it when a one-column file, unusual sample, or inconsistent export makes detection ambiguous.
  2. Quoted fields follow established CSV rules. A comma or line break inside double quotes remains part of one value, and two consecutive quotes become one literal quote. Empty physical lines are skipped, while an empty field between delimiters is preserved.
  3. Headers are trimmed and made unique. A blank heading becomes column_1, column_2, and so on. Repeated headings gain _2, _3 suffixes in appearance order. The result reports these renames instead of silently overwriting an earlier property.
  4. Rows shorter than the widest row receive empty strings for missing cells. When type inference is off, every parsed cell remains text. When enabled, true, false, null, and safe numeric syntax become JSON primitives; leading-zero identifiers such as 0012 remain strings.
  5. The output is a formatted JSON array that can be copied or downloaded. Input is limited to two million characters because very large datasets should use a streaming parser rather than occupying a browser textarea and duplicating the full dataset in memory.

When csv to json converter is useful

Multiline support export

A support note enclosed in quotes contains two paragraphs and commas. The parser keeps it as one note property instead of creating extra rows and columns.

Duplicate report headings

A report contains two columns named Total. The second becomes Total_2, and the repair count makes the changed property visible before the JSON enters another system.

Check the output

Questions about CSV to JSON Converter

Can it parse quoted commas and newlines?

Yes. Quoted delimiters, doubled quotes, and embedded line breaks are handled by a dedicated CSV parser rather than string splitting.

Why are numbers strings by default?

CSV carries text with no reliable type declaration. Keeping strings protects leading zeros, large identifiers, and values that merely resemble dates or numbers.

What happens to duplicate headers?

They receive numbered suffixes such as name_2. Blank headings receive column_N names. The result reports how many headings were renamed.

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