You are exporting the values, not the workbook

A workbook holds multiple sheets, formulas that compute, formats that control how values appear, merged cells, comments, validation rules, charts and frozen panes. A CSV holds rows of text separated by commas.

Everything on that first list has nowhere to go. What arrives in the CSV is the data — and only the data. That is the trade, and it is worth understanding before you rely on the output.

Formulas become their results

=SUM(A1:A10) becomes 500. The CSV records what the cell was displaying, not how it got there, so the logic is gone and the file cannot recalculate. Change an input and nothing updates, because there is nothing left to update.

One sheet at a time

A CSV is a single table, so only one sheet can be exported. A sheet selector appears when the workbook has more than one, and each has to be exported separately.

That is a genuine limit rather than a missing feature: combining sheets into one table would require decisions about how they relate that no converter can make for you.

Formatting disappears, and this is the one that surprises people

A cell showing 50% stores 0.5 with a percentage format on top. One showing $1,200.00 stores 1200. The format is the presentation, so what lands in the CSV is the underlying value — and it can look nothing like what was on screen.

So a column of percentages arrives as a column of decimals, and a column of currency arrives as bare numbers. Both are correct. Both will surprise whoever opens the file expecting what they saw in Excel.

Merged cells and layout

Merges resolve into ordinary cells, typically leaving blanks where the merge used to span. Hidden rows, frozen panes and column widths simply do not exist in the format. The data survives; the arrangement that made it readable does not, so a sheet that depended on visual structure can look broken at first glance while being entirely intact.

Dates, the classic hazard

A date in a spreadsheet is a number with a display format applied. The number is the day count; the format is what you see. So what appears in the CSV depends on how the cell was formatted, not on what a date "is".

The consequence is the familiar ambiguity: 01/02/2025 may mean the first of February or the second of January, and the CSV carries no clue which convention produced it.

Format dates as year-month-day in the workbook before exporting if the file is going anywhere else. It is unambiguous in every locale and it removes the entire class of problem at the cost of one formatting change.

Why it is still worth doing

• Everything imports CSV. There is no system that needs convincing.
• No software required to read it — a text editor, a shell, a script.
• It is small, being text.
• It works in version control. A CSV diffs line by line; a workbook is an opaque binary that does not.

The losses are losses of structure and presentation, not of the data. If the goal is moving values from one system to another, CSV does that job as well as anything can.

Treat the CSV as an export, never as the copy of record

Keep the workbook as the source of truth and the CSV as a snapshot of one moment. Editing the CSV and importing it back returns values without formulas, formatting or structure — you would be rebuilding what you already have, minus everything that made it useful.

When the data needs to change, change it in the workbook and export again. Everything here runs in your browser and the file is never uploaded. To build a workbook from plain text, the CSV to XLSX converter does that, with values only.