Convert CSV to JSON and JSON to CSV, with a table preview
Runs in your browser. Nothing you type is sent anywhere. Updated on 24 Oct 2026.CSV and JSON hold the same rows in different shapes, and converting between them is a daily chore. Both directions work here, with a table preview so you can check the columns before trusting them, up to 20 MB. Files are read on your own device.
Click the "CSV to JSON" or "JSON to CSV" chip at the top to pick the direction.
Paste the CSV rows or the JSON array into the left pane, or click Open file to load a .csv, .tsv or .json file.
For CSV to JSON, check Separator, Header row and Detect types, and choose Objects or Arrays.
For JSON to CSV, pick the Separator and keep "Write header" on to get a row of column names.
Check the Table preview, then click Copy JSON or Copy CSV, or the download icon to save the file.
This CSV to JSON converter reads comma, semicolon, tab or pipe separated data and turns it into a JSON array as you type, with a table preview so you can check the columns before you copy. Switch direction to turn a JSON array into CSV for a spreadsheet.
People use it to feed a spreadsheet export into an API, to seed a test database, or to turn a report from a bank or a payroll system into something a script can read. The reverse is common too: an API returns JSON and a colleague wants it in Excel.
The separator is detected from the data, and you can override it. The first row is used as column names unless you switch that off. Quoted fields, doubled quotes and line breaks inside quotes are handled as the CSV standard describes. Type inference turns 42, true and empty cells into a number, a boolean and null, but keeps values like 007 or a 19-digit account number as text so nothing is silently changed. When going to CSV, nested objects become dot-named columns and you are told which.
Everything runs in your browser; files you open are read on your device and never uploaded. Files up to 20 MB work comfortably. Ctrl+Enter copies the result. Related tools: JSON Formatter, YAML to JSON, JSON to TypeScript.
Paste the CSV or open a .csv file. The JSON appears as you type, with a table preview underneath. Choose array of objects or array of arrays, then press Copy or Download.
No. The file is read and converted by your own browser, so customer lists, bank exports and payroll data never leave your device. The tool is free and needs no account.
Values with leading zeros, such as 007 or a PIN code starting with 0, and integers too long for JSON to hold exactly, like account numbers, stay as strings. Converting them to numbers would change them. Turn type inference off to keep every value as text.
Yes. The separator is detected automatically from comma, semicolon, tab and pipe by testing which one splits the first rows evenly, and the one chosen is shown above the output. European exports that use a semicolon need no setting at all. Pick the separator yourself if detection guesses wrong.
Nested objects are flattened into columns with dotted names, so address.city becomes its own column. Arrays are written as JSON text inside a single cell. A note lists what was flattened so nothing changes silently.
Files up to 20 MB convert comfortably, which is the limit this page accepts. The table preview shows the first 100 rows so the page stays responsive, while the JSON or CSV you copy or download always contains every row of the file. Split anything larger before converting.
Still stuck? Ask about CSV to JSON and anybody who knows can answer. No account needed.
Same job, other tools: Query String Parser – Split a URL query string into a table of decoded parameters · Column Letter to Number – Find the column number of any Excel column letter, such as AB = 28 · Number to Column Letter – Turn a column number into its Excel letters, such as 28 = AB · JSON to Pydantic Model – Paste an API response and get Pydantic v2 BaseModel classes with field aliases · JSON to YAML – Turn JSON into clean, readable YAML for configs.
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Also works as: JSON to CSV · CSV to JSON Array.
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