Convertur
Guide

Working with Data Files: JSON, CSV & Spreadsheets

Move data between apps, APIs, and spreadsheets without losing your mind — or your columns.

3 chapters11 min totalUpdated Jun 2026
Chapter 01

JSON vs CSV, and when to use each

JSON describes nested, structured data and is what most APIs return. CSV is a flat grid of rows and columns that spreadsheets open natively.

Use JSON to move data between programs; use CSV the moment a human needs to sort, filter, or eyeball it.

Chapter 02

Flattening nested data

Spreadsheets can’t represent nesting, so converting JSON to CSV means flattening. A one-level flatten turns each object into a row and each key into a column.

Deeply nested values usually need to be summarised or split across columns before they make sense in a grid.

NoteDecide what a “row” means in your data before converting — usually it’s one object in the top-level array.
Chapter 03

Escaping and encoding gotchas

Commas, quotes, and line breaks inside a field will break a naive CSV. The fix is to wrap those fields in quotes and double any internal quotes.

Save as UTF-8 so accented characters and emoji survive the trip into your spreadsheet.