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GigaJSON

CSV to JSON

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Convert a CSV file into a JSON array, one object per row, keyed by the header. The delimiter (comma, semicolon or tab) is detected for you. Quoted fields that contain commas or line breaks are read correctly, and a value like 007 keeps its leading zeros.

How to use it

  1. Paste CSV with the column names on the first line, or open a .csv file.
  2. Check the JSON preview.
  3. Download or copy the JSON, or open it in GigaJSON to query or chart it.

Read more: Convert JSON to CSV: nested objects, arrays and Excel gotchas

Private, and made for big files

This tool runs in your browser, in a background worker: nothing you paste or open is uploaded, and nothing is kept after you leave. Input is limited to 128 MB. Processing runs in a background worker. If your connection drops while you're here, the tool keeps working. When one tool isn't enough, GigaJSON opens your data with a tree, a table, JSONPath/JMESPath/jq queries, transforms, diff and history.

Questions

Which delimiters are supported?

Comma, semicolon and tab. It picks whichever appears most in the header line.

Are numbers converted?

Plain numbers (42, 3.14, -1e3) become JSON numbers, and true/false become booleans. Everything else stays text, including 007, +5 and 1,5, so IDs and codes come through intact. Empty cells become null.

Is my data uploaded?

No. The tool runs in your browser, in a background worker. Nothing you paste or open goes to a server, and nothing is kept after you leave the page.

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