Converting Excel to CSV and CSV to Excel

Why the two formats aren't interchangeable, and what gets lost in the conversion.

Summary

CSV only stores plain data — formulas, colors, multiple sheets, and charts all get lost when converting to CSV. A system's data-import feature usually wants CSV, while Excel is better suited for reporting and presentation.

Step by step

Decide the direction: CSV for importing data into a system, Excel for building a report.
When going from Excel to CSV, be clear about which sheet you want, since CSV can only hold one at a time.
After converting, check that date and number formats weren't mangled in the process.
For Turkish characters, make sure the file is saved with UTF-8 encoding to avoid garbled text.

Why it matters

Most Excel and CSV conversions happen when moving data into another system: uploading a product list to an online store, importing customer accounts into accounting software, or sending a subscriber list to an email service. A small formatting issue can mean hundreds of rows imported wrong or not at all. You usually notice after the import, and undoing it takes time.

Regional settings can trip you up

In regions where the comma is the decimal separator, such as Turkey and much of Europe, Excel often saves CSV files with semicolons between fields. A system expecting commas will cram everything into one column.
A price like 1.250,50 can be misread by a system that treats the period as the decimal point.
For Excel to display accented or non-English characters properly, the file may need to be saved as UTF-8 with a BOM.

Common mistakes

Losing leading zeros. Postal codes, product codes and phone numbers get read as numbers and the leading 0 disappears. Format those columns as text.
Long numbers turning into scientific notation. A barcode can become something like 8.69E+12, and the last digits may be lost once saved.
Mixing up day and month. 03/04 is April 3 in one system and March 4 in another.
Opening a CSV in Excel and saving over the original, which makes all the above changes permanent.

A sample scenario

A boutique exports its product list from Excel to CSV and uploads it to its online store. Afterward, some product codes are missing their leading zeros and prices look a hundred times too high. The owner formats the product code column as text, rewrites the prices with the period separator the store expects, and saves the file as UTF-8. Before uploading the full list again, they test with a ten-row file and check the result.

When to get help

If you're importing into accounting or payroll software, remember that a bad import can affect financial records. Ask the software vendor or your accountant for the exact template the program expects, and run the import in a test environment first.