inyourbrowser.com

CSV ↔ JSON Converter

CSV to JSON converter is a browser-based data transformation tool that handles quoted fields, custom delimiters, and bidirectional conversion. Paste or drop a file and get structured JSON output instantly.

CSV Input
Output

CONVERT

First row is used as object keys. Quoted fields with commas are handled correctly.

Runs entirely in your browser

Dedicated pages

Direct links for each conversion direction.

CSV to JSON Converter
Convert CSV files to JSON instantly in your browser. Auto-detects headers. Free, private.
JSON to CSV Converter
Convert a JSON array to CSV format instantly in your browser. Free, private.
CSV to JSON Converter
Convert any CSV data into a JSON array directly in your browser. Handles quoted fields, free, and private. Runs in your browser.
JSON to CSV Converter
Convert JSON arrays to CSV format instantly in your browser. Handles quoted values and special characters. Free, runs in your browser.

How to convert CSV to JSON

  1. Paste your CSV data into the input area or upload a .csv file.
  2. The first row is automatically treated as the column header, toggle this if your CSV has no header.
  3. Choose between JSON array (default) or JSON object output.
  4. Click "Copy" or "Download" to get the converted JSON.

Common uses

  • Converting data exports from spreadsheet applications to JSON for APIs, then format the JSON output for readability
  • Transforming CSV reports into JSON for JavaScript applications
  • Preparing data for import into a database or no-code platform that expects JSON, use Base64 encoding if you need to embed the data in a URL or payload

Technical specification

  • Algorithm or formula: Custom hand-written CSV parser that handles quoted fields, escaped double quotes (""), embedded commas, and CRLF or LF line endings per RFC 4180. JSON output uses JSON.stringify with two-space indentation.
  • Browser API or library: Native JSON.parse and JSON.stringify. No external parsing library.
  • Input limits: Bounded by browser memory. Multi-megabyte CSV converts quickly on modern devices.
  • Output: JSON array of objects (default) or JSON object keyed by the first column. Reverse direction emits CSV with the appropriate delimiter.
  • Known limitations: Deeply nested JSON cannot round-trip through a flat CSV. Mixed delimiter detection assumes a single delimiter per file.

Frequently asked questions

Is my CSV data uploaded anywhere?
No. Conversion happens entirely in your browser.
What delimiter formats are supported?
The tool auto-detects commas, semicolons, and tab-delimited CSV. You can also set the delimiter manually.
Can I convert JSON back to CSV?
Yes. The tool supports both directions. Switch between CSV to JSON and JSON to CSV using the mode selector.
How are special characters handled?
Quoted fields containing commas, newlines, or quotes are handled correctly per the CSV standard (RFC 4180).

Reviewed and tested May 26, 2026.