Mapping messy CSV exports into nested JSON
How the Advanced Mapper turns flat spreadsheet columns into structured, nested objects.
7 MIN READ
Most CSV-to-JSON converters give you one flat object per row. That's fine until a client's export has repeating column groups — three shipping addresses, five line items — that really belong nested under a parent key.
Advanced Mapper lets you draw that structure explicitly: pick a column, assign it a path like `orders[].items[].sku`, and the tool builds the array nesting for you as it parses the sheet with Papaparse and xlsx.
It's slower to set up than a one-click converter, but it means the output actually matches the shape your API or database expects, instead of a flat dump you have to reshape by hand afterward.
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