Convert CSV to JSON and back. Pick comma, semicolon or tab, numbers and booleans are auto-typed, and quoted fields keep commas and newlines.
All conversion happens locally in your browser. Your data never leaves your device.
The parser reads your CSV character by character, tracking whether it is inside a quoted field. That means commas, semicolons and even newlines inside quotes are kept as part of the value, while the delimiter outside quotes splits fields. The first row becomes the set of keys for the JSON objects.
| CSV Value | JSON Type | Example |
|---|---|---|
| Integer | number | 42 → 42 |
| Decimal | number | 3.14 → 3.14 |
| true / false | boolean | true → true |
| Empty | null | → null |
| Anything else | string | "007" → "007" |
CSV (Comma-Separated Values) stores tabular data as plain text rows. JSON (JavaScript Object Notation) is a structured format for key-value objects and arrays. They are the two most common interchange formats for tabular data, and converting between them is a everyday task.
The first row is used as the header: each value becomes a key in the JSON objects. If a data row has fewer values than headers, the missing keys get null. If it has more, the extras are ignored.
Whole numbers and decimals become JSON numbers, the strings true and false become booleans, empty values become null, and everything else stays a string. Quoted fields, including values with embedded commas and newlines, are parsed correctly.
Comma, semicolon and tab. Semicolon is common in CSV files exported from European versions of Excel; tab is the standard for TSV files. Pick the delimiter that matches your file before converting.
No. All parsing and serialization happens in your browser with plain JavaScript. Nothing is sent to a server, so sensitive data stays on your device.
Round out your spreadsheet workflow: export workbooks as clean text with Excel to CSV, hand a finished file back to a colleague with CSV to Excel, sanity-check messy data in the CSV Viewer, or skip a step entirely with Excel to JSON.
If you just finished with CSV ↔ JSON Converter, the natural next steps are JSON Formatter & Validator, Base64 Encoder & Decoder, Text Diff, or browse every tool in Privacy File Tools.