Data & ConvertersRuns in your browser · files never uploaded

CSV to JSON

Structured CSV → JSON

4.5· 94 votes

A CSV-to-JSON converter parses a delimited file and maps each row to a JSON object keyed by the header row. StuHub auto-detects the delimiter (comma, semicolon, tab, pipe), handles RFC 4180 quoted fields, and runs entirely in your browser — large sheets never leave your device.

Your file never leaves this browser. Everything runs on your device — no uploads, no server storage, no retention.How it works →

CSV to JSON

Convert CSV to JSON and back with full RFC-4180 handling of quotes, escapes, and embedded newlines. Automatically detects the delimiter (comma, semicolon, tab) and header row. Great for ingesting spreadsheet exports into code, turning an API's JSON response into a CSV you can open in Excel, or moving data between systems that insist on different formats.

How to use

Paste CSV or JSON into the input panel.
The opposite format appears on the right.
Copy or download the converted output.

This tool requires JavaScript to interact. Enable JavaScript to use it in your browser.

Delimiter First row is header Auto-detect types✓ Valid

CSV input

JSON output

[
  {
    "name": "Ada Lovelace",
    "age": 36,
    "city": "London",
    "active": true
  },
  {
    "name": "Alan Turing",
    "age": 41,
    "city": "Manchester",
    "active": true
  },
  {
    "name": "Grace Hopper",
    "age": 85,
    "city": "New York",
    "active": false
  }
]

Preview — first 4 rows

name	age	city	active
Ada Lovelace	36	London	true
Alan Turing	41	Manchester	true
Grace Hopper	85	New York	false

What is CSV to JSON?

How do I use CSV to JSON?

Paste CSV or JSON into the input panel.
The opposite format appears on the right.
Copy or download the converted output.

CSV to JSON by the numbers

Delimiters: , ; tab |
Quoting: RFC 4180 (double-quote escape)
Header detection: Automatic + override
Max comfortable size: ~20 MB
Output: JSON array-of-objects or array-of-arrays

Common use cases for CSV to JSON

Importing an Excel export into a JSON API.
Prepping a user list for a config file.
Turning a survey export into a seed for a JSON database.
Flattening a product catalogue for a static-site generator.
Piping a support-ticket export into a dashboard.

Common pitfalls and how to avoid them

First row becomes data, not keys — Toggle "Has header" on. If the file genuinely has no header, keep it off and consume an array-of-arrays.
EU Excel exports split on the wrong character — Pick semicolon as the delimiter explicitly — commas are decimal separators in EU locales.
Quoted commas break parsing — Make sure quoted fields use " not curly quotes. Curly quotes come from Word; re-export from the original source.

When should I use CSV to JSON?

CSV ↔ JSON covers the common direction. For JSON → CSV only (with more flattening options), use JSON to CSV. For Excel (.xlsx) conversions, use Excel to CSV / CSV to Excel / JSON to Excel.

Frequently asked

Does the tool auto-detect the delimiter?

Yes. Comma, semicolon, tab, and pipe are detected automatically. You can override via the delimiter picker if detection gets it wrong.

What happens to the header row?

By default the first row becomes object keys ({ name, age, ... }). Disable "Has header" for an array-of-arrays output instead.

Does it handle quoted fields with commas inside?

Yes — RFC 4180 quoting is supported, including escaped double-quotes ("" inside a quoted field).

Is my file uploaded anywhere?

No. Everything runs in your browser. Your files never leave your device, and there is no server component for this tool.

Related in Data & Converters