CSV ↔ JSON Converter
Convert CSV to JSON or JSON to CSV instantly. Paste your data, pick the direction, and copy or download the result, no uploads needed.
CSV Input
JSON Output
How to convert between CSV and JSON
Pick a direction, paste your data, and copy or download the converted result.
- 01
Pick the direction
CSV → JSON turns rows into an array of objects. JSON → CSV turns an array of objects into rows, with a header line.
- 02
Paste the data
For CSV, the first row must be the column names and fields must be separated by commas. For JSON, the input must be an array, such as [{"name":"Asha"}].
- 03
Convert, then copy or download
Download saves the result as converted.json or converted.csv.
How tricky CSV is handled
CSV looks simple until a value contains a comma, a quote or a line break. The converter follows RFC 4180, the closest thing CSV has to a standard: a field wrapped in double quotes can contain commas and line breaks, and a doubled quote inside it stands for one literal quote. Windows (CRLF) and Unix (LF) line endings both work, and blank lines are skipped.
Here's a small CSV with all three awkward cases. The first row has a comma inside a quoted name and an escaped quote in the note, the second has a line break inside the note, and the third has an empty city:
| CSV field | Becomes in JSON |
|---|---|
| "Sharma, Asha" | "name": "Sharma, Asha" |
| "Said ""hi""" | "note": "Said \"hi\"" |
| "line one⏎line two" | "note": "line one\nline two" |
| (empty) | "city": "" |
Every value comes out as a string, including numbers and true or false. That's deliberate, since CSV has no types and "00123" or "1e5" shouldn't silently change. Convert specific columns to numbers in your code if you need them.
Going from JSON to CSV
The columns are every key found in any object, in the order they first appear, so rows with different fields still line up. A row that lacks a key gets an empty cell. Values with commas, quotes or line breaks are quoted automatically.
Nested objects and arrays can't be split into columns, so they're written as JSON text inside the cell: {"d":3} becomes "{""d"":3}" in the CSV. If you need them as separate columns, flatten the JSON first, for example turning address.city into its own key.
When you'd convert
Spreadsheet data into an API
Export a sheet as CSV, convert it to JSON and paste it into an API request or a seed file.
API data into a spreadsheet
Convert a JSON array to CSV and open it in Excel or Google Sheets to filter, sort and chart it.
Quick test fixtures
Write a few rows in a spreadsheet, then convert them into JSON test data for your code.
Limits worth knowing
- Commas only. Files using semicolons, common in European Excel exports, or tabs need converting first: find and replace the separator, or re-export as comma-separated.
- The first row is always treated as headers. Duplicate header names overwrite each other in the JSON.
- No type detection: numbers, booleans and dates stay strings in CSV → JSON.
- Large files are held in memory. A few megabytes is fine; a 200 MB export is better handled with a script or a database import.