Prepare API input
Convert spreadsheet exports into JSON records for testing, migration or scripting.
100% local · files never leave your browser
Convert tool
CSV to JSON Converter
Convert CSV rows to structured JSON in your browser while preserving headers, quoted commas and values.
✓ Free to use✓ No signup✓ Runs locally
73 bytes · local only
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Processed entirely in this tab
Your input and result are not sent to JSON Hearth or stored on a server.
When to use it
What CSV to JSON helps you do
CSV-to-JSON conversion uses the header row as object keys and turns each following row into a JSON record.
Inspect CSV structure
Confirm how headers and quoted fields will map before building an importer.
Create development fixtures
Turn a small table into JSON examples for local development and tests.
How it works
CSV to JSON, without the upload.
Add your data
Paste a value, open a local file or begin with the working sample.
Run the tool
The transformation executes in your browser, not on our servers.
Review the result
Check the output, then copy or download it for your next task.
Important limitations
What to check before using the result
Review required
CSV does not preserve rich data types reliably, so numeric and boolean-looking values may need review.
Review required
Inconsistent row lengths or unusual dialects can require cleanup before conversion.
Common questions
About CSV to JSON
Does CSV to JSON Converter upload my data?
No. Your input is processed by code running in your browser and is not sent to an application server.
Is CSV to JSON free to use?
Yes. The tool is free, requires no account and can be used directly in the browser.
Does CSV preserve numbers and booleans?
CSV cells are text-oriented. Review inferred or converted values when precise types matter.
Can CSV fields contain commas?
Yes. Properly quoted fields can contain commas, line breaks and quotation marks.