CSV to JSON
Convert CSV / TSV data into structured JSON — auto-detects delimiter
CSV Input
JSON Output
CSV to JSON — Complete Guide & Instructions
MakeCard CSV to JSON turns spreadsheet rows into a structured JSON array in one click. Paste CSV or TSV data and the delimiter is auto-detected — comma, tab or other separators all work. Keep “First row is the header” checked to use column names as object keys (blank headers fall back to col1, col2…), or untick it for a plain array of arrays; then copy the pretty-printed result straight into your code.
How to Use CSV to JSON
- 1 Paste your CSV/TSV data into the input box — or press Sample for an example.
- 2 Leave “First row is the header” ticked so columns become JSON keys.
- 3 Press “Convert to JSON”.
- 4 Check the info line — it reports the detected delimiter and row count.
- 5 Copy the JSON output from the result card into your app, API test or file.
Key Features & Capabilities
- Automatic delimiter detection — commas, tabs and other separators.
- Header-row mode produces objects keyed by column names.
- Headerless mode produces a clean array of arrays.
- Blank headers auto-named col1, col2, col3…
- Detected delimiter and row count shown in the info line.
- Sample data button plus one-click copy of pretty-printed JSON.
Supported Formats & Specifications
| Parameter | Specification |
|---|---|
| Input | CSV, TSV or delimited text (paste) |
| Delimiter | Auto-detected |
| Output | Pretty-printed JSON (2-space indent) |
| Modes | Header objects or array-of-arrays |
| Processing | Instant, in-browser |
Practical Everyday Use Cases
- Converting exported spreadsheet data for an API or seed script.
- Turning a CSV product list into JSON for a frontend.
- Quick data transformation for analysts without writing a parser.
- Feeding tabular data into tools that only accept JSON.
- Prototyping API payloads from real spreadsheet rows.
Pro Tips for Best Results
- Values convert as strings — cast numbers server-side or in your code if types matter.
- Check the info line for the detected delimiter; a wrong-looking result usually means an unexpected separator.
- Quoted fields containing commas are handled by the parser — paste real-world exports without pre-cleaning.
- For the reverse direction, the JSON to CSV tool converts arrays back to rows.
Common Problems & Solutions
The detected delimiter does not match your data — check the info line; mixed separators confuse detection, so normalise to commas first.
The header checkbox is off or your first row is blank — tick “First row is the header” and ensure the first line holds column names.
Privacy & Security
100% Client-Side Execution
Conversion runs entirely in your browser — your spreadsheet data is never uploaded or logged.
Frequently Asked Questions
Everything you need to know about using CSV to JSON
Paste the CSV above and press Convert to JSON — each row becomes an object keyed by the header row, output as a JSON array.
Yes — the delimiter is auto-detected, so tabs, commas and other separators all parse correctly.
Untick “First row is the header” — the output becomes an array of arrays instead of keyed objects.
Values are emitted as strings — JSON has no type inference here, so cast them in your application if you need numeric types.
No — parsing and conversion happen in your browser; nothing is sent to a server.
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