Row Zero supports a variety of file formats including CSV, TSV, TXT, Parquet, JSONL, and XLSX. Note that XLSX files will import the data, but may not fully import charts, pivot tables, obscure functions, macros, or VBA. Row Zero also automatically unzips and opens compressed .gz files.
Note that Row Zero can open much larger files than other spreadsheets, so you can open files that Excel can’t open.