It also offers you batch file conversion. You can convert more than one JSON file into Excel format in one go. For this, you have to upload all the JSON files to their server one by one. After ...

How to convert an XLS file to CSV Let’s say you have the file clients.xlsx and you need it converted to clients.csv to be then uploaded as a client list in your new CRM tool.

That shouldn't be a problem, after all, Excel can handle JSON. So, you try to open the file in Excel using its data import tooling, which usually works very well indeed as a basic ETL system.