CSV to JSON Converter
Convert comma-separated records into JSON objects while preserving quoted commas, multiline cells and leading zeros.
Processing stays in this browser. Inputs are not sent to a tool-processing server or saved by this utility. Limit: 500,000 characters per input.
How to use CSV to JSON Converter
- Paste comma-separated CSV with a header row.
- Convert and inspect the JSON array. All cell values remain strings.
- Verify headers and row counts before using the result as a fixture or import.
A reproducible example
Use Load example to try this input, then change one value and inspect the result.
id,name,note
001,Ada,"API, backend"
002,Lin,"Said ""hello"""Preserve identifiers and dates
This converter leaves cells as strings. The id 001 stays "001", a large account number keeps its digits and a date is not silently converted to a timezone-dependent value. Apply your application schema after conversion when numeric or boolean types are required.
Handle quoted fields correctly
A comma inside a quoted field belongs to the value, not to the column separator. Two double quotes inside a quoted field represent one double quote. Newlines inside quoted cells are retained. The parser accepts LF and CRLF record endings and removes a UTF-8 byte-order mark at the start.
Reject ambiguous tables
The first row defines the keys. Empty or duplicate header names are rejected because they would hide values when creating an object. Every data row must have the same number of columns as the header. A single final newline is accepted; blank records in the middle are treated as rows and checked.
Choose the right import format
This tool accepts comma-delimited CSV, not tab-separated text or semicolon-separated regional exports. It does not infer nested objects from dotted headers. For a large export, streaming conversion in your own application avoids browser memory limits and lets you validate each record against your schema.
Common questions
Will 001 become a number?
No. Cell values remain strings; add schema-aware conversions afterward.
Can this execute spreadsheet formulas?
No. It treats cells as text. Review formula handling separately if you later export the data to a spreadsheet.
Read the format or engine documentation. Found an edge case? Send a small reproducible example.