CSV to JSON Converter
Transform flat CSV rows and tables into structured JSON arrays of objects or 2D matrices with automatic type detection and zero server latency.
Drag & drop a CSV/TSV file, or browse
Instant parsing for files up to 50 MB
What is a CSV to JSON Converter?
A CSV to JSON converter is a developer utility that parses tabular, comma-separated values (CSV) into structured JavaScript Object Notation (JSON). It converts the first row of column headers into object keys and maps subsequent data rows into structured JSON records with automatic typing for numbers, booleans, and null values.
How to convert CSV to JSON online
- Paste or load your CSV: Drop your CSV file into the upload zone or paste the raw CSV rows directly into the source textarea.
- Choose output structure: Select Array of Objects for standard web and API payloads, or 2D Array for compact matrix serialization.
- Configure type casting: Keep auto-detection enabled to automatically convert numeric strings (
"42") to real numbers (42) and boolean flags to true/false. - Export or copy: Click Copy to place the JSON into your clipboard or Download .json to save the file.
Array of Objects vs 2D Array Output
| Output Style | Structure Example | Best Used For |
|---|---|---|
| Array of Objects | [{ "id": 1, "name": "Alice" }] | REST APIs, GraphQL, MongoDB, NoSQL document stores |
| 2D Array (Matrix) | [["id", "name"], [1, "Alice"]] | Compact payloads, charting libraries, spreadsheet engines |
Need the reverse transformation? Use our JSON to CSV Converter to flatten APIs back into spreadsheets, or format your JSON with our JSON Formatter.
Frequently asked questions
Does this tool automatically parse numbers and booleans?
Yes. With the "Auto-detect Data Types" option enabled, numeric values (integers, floating points) are converted to native JSON numbers, "true"/"false" are parsed as booleans, and empty cells are output as null instead of raw strings.
What JSON formats can I export?
You can choose between an Array of Objects (ideal for REST APIs, MongoDB, and web development) where column headers become object keys, or a 2D Array (compact format containing a header array followed by value arrays).
Can I convert large CSV files with thousands of rows?
Yes. The converter processes files efficiently in browser memory and provides a responsive preview without freezing your page.
Are my CSV files uploaded to any external server?
No. All parsing and JSON generation happens 100% locally in your browser. No files, records, or personal information ever leave your computer.
How does it handle comma-separated values inside quotation marks?
The engine strictly adheres to RFC 4180 standards, correctly preserving commas and escaped quotation marks ("") that are enclosed within quoted fields.