CSV to JSON

How to use the csv to json

1. Paste your CSV or open a file.
2. Check the delimiter and header settings.
3. Copy or download the JSON.

About this tool

Each row becomes an object keyed by the header row, which is the shape almost every API and script expects. Quoted fields are handled properly, including commas inside quotes and doubled quotes as an escape — the two things that break naive splitting on commas.

The delimiter is detected by looking at how consistently each candidate divides the first lines, so European semicolon files and tab-separated exports work without configuration. Type conversion turns <code>12</code> into a number and <code>true</code> into a boolean, but deliberately leaves values with leading zeros as text, because those are almost always identifiers — a postcode or phone number, not a number to do arithmetic on.

Rows with the wrong number of fields are reported rather than silently mangled; that mismatch usually means an unescaped quote somewhere above.

Common uses

• Turning a spreadsheet export into seed data.
• Preparing rows for an API that expects JSON.
• Inspecting a CSV as structured data.

Frequently asked questions

Why did my postcode lose its leading zero — or keep it?

It keeps it. Values with a leading zero stay text precisely because they are usually identifiers rather than numbers. Turn off type conversion to keep every value as text.

Does it handle commas inside quoted fields?

Yes, along with doubled quotes as an escape and both CRLF and LF line endings, per RFC 4180.

Is there a size limit?

Files up to about 20 MB open comfortably; larger ones depend on your device's memory. Nothing is uploaded, whatever the size.