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CSV to JSON Converter That Preserves Leading Zeros
Read quoted CSV cells, newlines and headers, then export JSON. Keep strings and leading zeros by default or choose explicit type-conversion options.
Result · JSON
Convert a document to preview its complete output.
Getting started
Choose the actual delimiter, paste or load a CSV, choose missing-cell behavior and download JSON.
Before you use the result
Headers are trimmed and must be nonblank and unique. Values stay strings; JSON export does not infer dates, booleans or numbers. Maximum 10,000 data rows.
Try an example
Convert id,name 001,"Li, Mei" to [{"id":"001","name":"Li, Mei"}] without losing the zero prefix.
How it works
A bounded quote-aware parser handles BOM, CRLF, embedded line breaks and doubled quotes. Missing cells become an empty string or null; extra cells are rejected.
Frequently asked questions
Read quoted CSV or TSV locally and preserve leading zeros as strings.
How do I use CSV to JSON Converter?
Choose the actual delimiter, paste or load a CSV, choose missing-cell behavior and download JSON.
Does this tool upload my data?
Inputs and files are processed in your browser. Page-view analytics do not contain your tool input.
What should I check before using the result?
Headers are trimmed and must be nonblank and unique. Values stay strings; JSON export does not infer dates, booleans or numbers. Maximum 10,000 data rows.