Text & code · runs locally

Convert CSV to JSON

Headers become keys, rows become objects — with a header toggle for files that are all data.

Runs on your device No uploads, ever Free, no account
  1. 1
    Drop a CSV or paste it

    Quoted fields, commas inside quotes, whichever line ending — handled properly.

  2. 2
    Say how it's built

    First row as headers (the usual), or array-of-arrays for raw data.

  3. 3
    Take the JSON

    Pretty-printed by default, one line if you switch it.


Questions people actually ask

Numbers — string or number?

Numbers that look like numbers become numbers; everything else stays a string. Leading zeros are kept as strings, because they mean something.

What about really big CSVs?

Tens of MB are fine. Beyond that your laptop starts doing the hard work, not the tool — but it will get there.


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