Convert CSV to JSON Online

Free, privacy-first CSV to JSON converter. Transform CSV files to JSON format directly in your browser. No uploads, no servers, no sign-up.

Why Use ExploreMyData for CSV to JSON

Outputs Newline-Delimited JSON

Each CSV row becomes one JSON object per line. NDJSON is easy to stream, grep, and pipe into tools like jq, Python, or BigQuery.

No Upload Required

Your CSV file stays on your device. No data is sent to any server. Everything runs locally in your browser using DuckDB WASM.

Auto-Detects Column Types

Numbers, dates, and booleans are detected automatically. They export as native JSON types, not quoted strings, so downstream parsing works correctly.

Transform Before Export

Filter rows, rename columns, aggregate data, or add calculated fields. Shape your data before converting it to JSON.

Free Forever

No sign-up, no trial, no watermarks. Convert as many CSV files to JSON as you need, completely free.

Works Offline

Once loaded, ExploreMyData works without an internet connection. Convert CSV to JSON even on a plane.

How It Works

1

Drop your CSV file

Drag a .csv or .tsv file onto the page. It loads instantly.

2

Transform (optional)

Filter rows, rename columns, or reshape the data before export.

3

Export as JSON

Click Export, choose JSON, and download your NDJSON file.

Frequently Asked Questions

How do I convert CSV to JSON?

Open exploremydata.com/app, drag your CSV file onto the page, then click Export and choose JSON. Each row becomes a JSON object, output as newline-delimited JSON (NDJSON).

What JSON format does it output?

ExploreMyData outputs newline-delimited JSON (NDJSON), where each line is a standalone JSON object representing one row. This format is widely supported by data tools and easy to stream-process.

Can I filter rows before converting?

Yes. You can filter, sort, aggregate, pivot, and apply 32+ transformations to your CSV data before exporting. Only the rows matching your filters will appear in the JSON output.

Does it preserve data types?

Yes. ExploreMyData auto-detects column types (numbers, dates, booleans, text) from your CSV. Numbers export as JSON numbers, not strings, so downstream tools parse them correctly.

Ready to convert your CSV to JSON?

No sign-up, no upload, no tracking. Just drop your file and export.

Convert CSV to JSON Free