📖 What is CSV to JSON?
CSV to JSON converts comma-separated values into a JSON array of objects, using the first row as property names. Each subsequent row becomes a JSON object with key-value pairs matching the headers.
Use it to prepare spreadsheet data for API requests, convert database exports into JSON for web applications, or transform CSV files into a format your code can easily parse. Everything runs in your browser — your data is never uploaded.
💡 Example
Input
name,age,city
Alice,30,NYC
Bob,25,London
Output
[{"name":"Alice","age":30,"city":"NYC"},
{"name":"Bob","age":25,"city":"London"}]
🛠️ Common Use Cases
- Preparing spreadsheet data for REST API POST requests
- Converting database CSV exports into JSON for web applications
- Importing Excel data into MongoDB, Firebase or other JSON-based stores
- Transforming CSV log files into structured JSON for analysis
- Building JSON seed data for testing from spreadsheet templates
📝 How CSV Parsing Works
The parser follows the RFC 4180 standard: commas separate fields, double quotes wrap values that contain commas or newlines, and two consecutive double quotes inside a quoted field represent a literal quote. The first row is always treated as headers.
Numeric values are auto-detected and converted to JSON numbers. Values that look like true/false become JSON booleans. Everything else stays as a string.
⚠️ Common Mistakes
- No header row — if your CSV has no headers, the first data row gets used as keys, producing meaningless property names
- Tab-separated data — TSV files use tabs, not commas. Replace tabs with commas first, or check if the tool auto-detects the delimiter.
- Trailing commas — extra commas at the end of rows create empty fields. Clean the CSV before converting.
- Mixed encodings — CSV files from Excel may use Windows-1252 encoding. Save as UTF-8 CSV for correct Unicode handling.
❓ Frequently Asked Questions
Does it auto-detect data types? ▾
Yes — numeric values become JSON numbers, true/false become booleans, and everything else stays as a string. If you need all values as strings, you can post-process the JSON output.
Can I convert TSV (tab-separated) data? ▾
This tool expects comma-separated input. For TSV data, replace all tabs with commas before pasting, or use a text editor find-and-replace.
What happens with empty cells? ▾
Empty cells become empty strings in the JSON output. If you need them as null values, you can find-and-replace "" with null in the output.
Is my data private? ▾
Yes — all processing runs entirely in your browser using JavaScript. Your data is never sent to any server.
Is this tool free? ▾
Completely free — no login, no usage limits, and it works offline once the page is loaded.
Yes — completely free, no login required, no usage limits.
Is my data private? ▾
Yes — all processing runs in your browser. Your data is never sent to any server.
Does it work offline? ▾
Yes — once the page is loaded, the tool works without an internet connection.