How to convert Excel to CSV, free and online

CSV is the format almost every system accepts. If you are importing contacts into a CRM, loading data into a database, or handing a file to a developer, you will usually be asked for CSV rather than Excel.

Converting is straightforward. Knowing what gets lost on the way is the part worth reading.

What CSV is, and what it is not

A CSV file is plain text. Each line is a row, and commas separate the values. That is the entire format.

This simplicity is exactly why it is universal — and exactly what it costs you. A CSV holds values and nothing else: no formulas, no formatting, no colours, no multiple sheets, no charts. Converting an Excel file to CSV is a deliberate act of throwing away everything except the data.

Converting in your browser

1. Open the spreadsheet tool Go to the free spreadsheet. No sign-up required.
2. Open your .xlsx file Drag it onto the page, or use the Open file button. Your data appears in the grid, with formulas read back as formulas.
3. Check the data Confirm the right sheet loaded and the values look correct. This is the step people skip and regret.
4. Export as CSV File → Export as CSV. Choose where to save it, and you are done.

Formulas become values

This surprises people. If cell D2 contains =B2*C2 and shows 450, the CSV will contain 450 — not the formula.

That is correct behaviour, because CSV has no concept of a formula. But it means the CSV is a snapshot. Change the source numbers later and the CSV does not update. Always export again rather than reusing an old file.

Common pitfalls

Only one sheet is exported

A CSV file holds exactly one table. If your workbook has several sheets, you need one CSV per sheet — export them one at a time.

Leading zeros disappear

A postcode or product code like 00123 can be interpreted as the number 123, losing the zeros. Formatting the column as text before exporting, or prefixing values with an apostrophe in Excel, avoids this.

Commas inside your data

If a cell contains a comma — an address, for instance — a naive export would break the row into extra columns. Proper CSV writers wrap such values in quotation marks. Ours does, but it is worth opening the result in a text editor to confirm when the data matters.

Dates change shape

Excel stores dates as numbers and displays them according to your locale. Once in CSV, a date is just text, and whatever reads it next may interpret 03/04/2026 as 3 April or 4 March. If the destination allows it, use ISO format (2026-04-03), which is unambiguous.

Going the other way

The same tool imports CSV. File → Import CSV loads a file into the grid, where you can add formulas and formatting, then export to .xlsx if you need a real Excel workbook.