CSV to JSON
Convert header-based CSV to a JSON array locally.
Free. No signup required.
What this tool does
Convert CSV rows into JSON objects using your headers as keys. Keep cell values as strings and preserve leading zeros with local browser processing.
How to use
Paste comma-separated CSV with a unique header row. Each row becomes a JSON object.
Features
Use the header row as object keys and preserve cell values as strings.
When to use it
Build a JSON fixture from a CSV export while keeping postal codes and leading zeros.
Example and checks
The header supplies object keys; the code remains a string so its leading zeros survive. Use unique headers and consistent column counts. CSV does not describe application types, so convert booleans or numbers only after deciding the destination schema.
name,code
demo,0012
[{"name":"demo","code":"0012"}]Common questions
Are numbers automatically converted from strings?
Cell values stay strings, preserving leading zeros. Rows must have the same number of cells as the header.
Data processing
This tool processes its input locally in your browser without sending it to a server for processing. Input and results are not included in share URLs.
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