CSV to JSON Converter
Convert comma-separated data into JSON objects using the first row as headers, or export each row as an array. Every cell stays a string, so values such as 00042 and 02108 keep their leading zeros. Quoted commas, escaped quotes, and line breaks are supported.
Converted JSON will appear here.
What this tool helps with
Spreadsheet exports often contain identifiers, postal codes, and account numbers that look numeric but must retain leading zeros. Type guessing can silently change these values during conversion.
How to use it
- Paste CSV text and select whether its first row contains headers.
- Choose Convert.
- Check identifier fields and quoted values in the result, then copy or download the JSON.
Requirements
A UTF-8 CSV or pasted text. Delimiter detection supports commas, tabs, or semicolons.
Limits and privacy
Blank rows are skipped. When headers repeat or are blank, a stable column name is generated. This does not infer data types: all cells remain strings. Convert only fields whose numeric meaning is clear in the application that consumes the JSON. Inputs are processed locally in this browser. The site does not provide an upload endpoint for this tool.
Frequently asked questions
Will CSV to JSON keep leading zeros?
Yes. Cells remain strings, so a postal code such as 02108 or an ID such as 00042 stays intact in the JSON output.
Are number-looking values converted to numbers?
No. CSV does not define a universal type for each cell. Values remain strings so identifiers and leading zeros are not silently changed.
Is a spreadsheet uploaded?
No. Conversion runs in this browser tab.
Step-by-step guide
Convert CSV to JSON without losing identifiers →