JSON to CSV Converter

JSON to CSV Converter takes an array of objects and produces a CSV you can open in Excel, Google Sheets or Numbers. It is the step between an API response and somebody who wants to look at the data in a spreadsheet.

Two things make this conversion harder than it looks, and both are handled here. The first is that JSON objects need not all have the same keys: one record has a middle name, the next does not. The columns are built from the union of every key seen, so nothing is silently dropped and missing values become empty cells rather than shifting the row.

The second is nesting. CSV is flat and JSON is not, so an object inside an object has to go somewhere. Nested fields are flattened into dotted column names, so a user object containing an address containing a city becomes a column called user.address.city. Arrays are either expanded into numbered columns or joined into one cell, whichever you choose.

Quoting is handled properly throughout. A field containing a comma, a quote mark or a line break is wrapped and escaped the way the CSV convention requires, so the file opens correctly instead of exploding into the wrong number of columns.

Everything runs inside your browser. Nothing you paste is uploaded, logged or stored, which matters when the input is a client list, an internal URL map or anything else you would not post publicly.

• Builds columns from every key across every record
• Flattens nested objects into dotted column names
• Arrays expanded into numbered columns or joined into one cell
• Correct quoting for commas, quotes and line breaks
• Comma, semicolon or tab output
• Clear parse errors that point at the problem
• Runs entirely in your browser

The json to csv converter is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

• Getting an API response into a spreadsheet
• Handing data to somebody who does not read JSON
• Preparing a data export for a bulk import form
• Checking a JSON file by eye in a familiar layout
• Producing a quick report from a log file