CSV to JSON Converter
Convert CSV tables into JSON arrays of objects with nested dotted headers
Accepted upload: .csv · max 5 MB. Uses the first row as headers. Dotted headers (e.g. address.city) become nested objects. JSON-looking cells parse back into arrays or objects.
CSV input
Paste or upload CSV
JSON output
Convert result
Frequently asked questions
Common questions about the CSV to JSON Converter.
How does the CSV to JSON Converter read my file?
The first row is treated as headers. Each following row becomes one JSON object. Empty cells become null. Quoted fields follow RFC 4180, including commas and newlines inside quotes.
How are nested objects rebuilt?
Dotted headers such as address.city become nested objects: { "address": { "city": "…" } }. Cells that look like JSON arrays or objects are parsed back into structured values.
Does my CSV leave my device?
No. Conversion runs entirely in your browser. ToolsArk does not upload your CSV for conversion.
Why did conversion fail?
Usually the CSV is empty, is not a table (needs a header plus at least one data row), contains an unclosed quoted field, or is larger than 5 MB. Fix the reported error and try again.
Can I download or copy the JSON?
Yes. After a successful conversion you can copy the JSON to the clipboard or download a .json file. You can also upload a .csv file as input.
Need to go the other way?
Use the JSON to CSV Converter to flatten JSON objects into CSV. Both tools share the same conversion engine and keep your data on this device.
Tags
Continue with these utilities
People frequently use these utilities together.