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How to convert Excel to CSV on a Mac
By Himanshu Ranjan · Updated 8 November 2026
Select the spreadsheets in Finder, open FileDial and choose Convert › Convert to CSV. You get one CSV per sheet with values only and no formatting. It runs offline on your Mac, needs no Excel, and works on many files at once.
What you get
CSV is plain text: one row per line, values separated by commas. FileDial's Convert › Convert to CSV writes one CSV per sheet, values only, no formatting. A workbook with three sheets becomes three CSV files.
Expect numbers to be numbers and text to be text. Colours, column widths, merged cells and number formats are gone, and formulas are replaced by values, which is exactly what you want when feeding a database, a script or an import form.
Steps
The steps are the same for one workbook or a folder of them.
- Select one or more .xlsx or other spreadsheet files in Finder.
- Hold the right Option key to open the dial and choose Convert, then Convert to CSV.
- Open the CSV files in a text editor to check the header row and any commas inside values.
- For other targets, Convert › Convert to TSV writes tab-separated files and Convert › Convert to JSON writes one JSON file per sheet.
CSV pitfalls worth knowing
CSV looks simple and is not. The format was only loosely standardized in RFC 4180 in 2005, it does not declare its text encoding, it has no type information, and a field that contains a comma, a quote or a line break has to be wrapped in double quotes. A CSV cannot safely be parsed by splitting on newlines.
Practical consequences: open the file in a text editor before importing it somewhere, check that accented characters survived, and be aware that Excel itself uses a dialect that differs from the standard. If an import chokes, Developer › Convert to UTF-8 and Developer › Remove BOM are available.
Built-in alternatives
Numbers can open an Excel file and export CSV: File > Export To > CSV, where you can choose one file per table or a combined file and change the text encoding under Advanced Options. If you have Excel, File > Save As with a CSV format works for the current sheet only, which is the main reason multi-sheet workbooks are annoying.
These routes are fine for one workbook. For many workbooks, or when each sheet must become its own file, FileDial does it in one pass.
Privacy
Spreadsheets hold customer lists, payroll and financial figures. Online converters require uploading all of it. FileDial runs on your Mac and works with Wi-Fi off, so the data stays on disk.
Choosing between CSV, TSV and JSON
CSV is the lowest common denominator, and it is not the only plain-text choice. TSV uses tabs, which avoids trouble when values contain commas. JSON keeps a clear key for every value. Pick by destination: databases and BI tools usually want CSV, scripts and web apps often want JSON, and tools that choke on commas in text are happier with TSV.
All three come from the same selection. Convert › Convert to TSV writes one TSV per sheet, values only, no formatting. Convert › Convert to JSON writes one JSON file per sheet and uses the first row as keys.
- CSV: universal, check quoting and encoding
- TSV: safer when text contains commas
- JSON: best when another program reads it by column name
Common mistakes and when FileDial fits
Open the CSV in a text editor, not in a spreadsheet, and read the first ten lines. Confirm the header row, check that quoted fields look right and that numbers have no stray symbols. If sheets have merged cells, the merge is flattened, so the value may appear only once. If the sheet has hidden header rows or notes above the table, delete them in the spreadsheet before converting.
A common surprise is a sheet that looks like one table but is really two tables side by side. A CSV is a single rectangle, so split the data into separate sheets first.
Choose it when you have many workbooks, when you want every sheet written out as its own file, or when you do not have Excel. It is quick and local.
Choose the spreadsheet app when you need control over the export: a specific delimiter, a chosen encoding or a particular sheet only. Numbers lets you select one CSV per table or a combined file and change text encoding under Advanced Options. Excel can save the active sheet as CSV. Neither route handles many files well, and that is the gap the batch tool fills.
Finally, name the output with intent. Each CSV takes its sheet's identity from the workbook, so check the file names after conversion, and use Rename › Add date prefix if the files will be dropped into a shared folder where several exports accumulate.
Questions
Does Convert to CSV keep formulas and formatting?
No. The tool writes values only, with no formatting, so formulas become their values and colours, widths and number formats are gone. That is what most imports want. If you need to keep formulas and layout, keep the workbook and only export CSV for the destination system.
What happens to a workbook with several sheets?
You get one CSV per sheet, as the tool's note says, so a three-sheet workbook yields three files. If you need them merged into one, make sure the sheets have the same header and use Data › Merge CSVs on the results, in the order you want the rows.
Do I need Excel installed to convert XLSX to CSV?
No. FileDial converts on its own and works offline, so you do not need Excel. Numbers can also export CSV from an Excel file through File > Export To > CSV, which is a good built-in option for a single workbook if you prefer to stay inside Apple's apps.