Decimal comma or column separator in CSV prices?

A price like 12,50 looks simple. In a CSV file the comma may be a decimal mark, or it may split the row into an extra column. The same character has two jobs, so the file alone does not always tell you which one it is doing.

Step 1: Keep the original file untouched. Save the file as you received it and never edit it. Work only on a copy. If something goes wrong, you can go back to the original.

Step 2: Confirm the price format your target system expects. Find out what the system you are importing into wants: the decimal mark (a dot, 12.50, or a comma, 12,50); the thousands separator (none, a comma, a dot or a space); the column separator (comma, semicolon or tab); and whether text and numbers containing the separator must be wrapped in double quotes.

To read your file, look at the header row and see which character sits between the column names. Then count the fields in a few data rows. If a row has more fields than the header, a comma inside a price is probably being read as a separator. A value like 1,250 is ambiguous: it could be one thousand two hundred fifty or one and a quarter. Do not guess. Check the source or ask whoever exported the file.

Step 3: Fix only the copy. Fix each affected row on its own, after you know which reading is correct. Two safe options: change the price to the format the target expects (12,50 becomes 12.50), or keep the value and wrap it in double quotes, if the target accepts quoted values in that format.

If the whole file uses a different column separator than the target expects, re-export it with the right separator. Do not swap characters by hand. Do not run a bulk find-and-replace on commas: it will also change commas inside product names and descriptions and can quietly damage rows that were fine.

Step 4: Recheck. Run your checks again on the corrected copy. Confirm that every row has the same number of fields as the header and that each price reads the way you intended. Compare a few rows against the original. If anything looks off, go back to the original and try again.

If you want a general look at your product CSV before importing, the free CSV check is available. It is a general file check, not a price audit. Confirm your price format yourself using the steps above.