CSV to Excel converts comma separated, semicolon separated and tab separated text files into a real Excel workbook. Opening a CSV directly in Excel looks simple, but Excel guesses at every value as it opens the file and many of those guesses are wrong. ZIP codes like 02134 lose their leading zero, phone numbers lose the plus sign, long order and card numbers turn into 1.23457E+15 and lose their last digits, product codes such as 3-4 or MAR1 become dates, and accented letters appear as é when the file is UTF-8. A file written with semicolons opens as a single column on a computer set to English, and a comma file does the same on a computer set to most European languages. This tool reads the CSV itself, detects the separator and text encoding, and writes an .xlsx in which nothing is guessed. Plain numbers such as prices, quantities and amounts are stored as numbers so they can be summed and sorted, while any value with a leading zero, a plus sign or more than fifteen digits is stored as text, exactly as written. Line breaks inside quoted cells, doubled quotes and empty fields are handled according to the CSV standard. The first row can be made a bold, frozen header, and column widths are set from the content. Several CSV files can be converted at once, either into one workbook with a sheet for each file, which is handy for monthly exports, or into separate workbooks in a ZIP. Everything runs locally, so customer lists, bank exports and payroll data stay on your device. The reverse conversion is Excel to CSV Converter, and to combine many CSV files into one long table instead of separate sheets use Merge CSV Files.
CSV is the most common way data leaves an application: banks, online shops, analytics tools, CRMs, accounting programs and databases all export it, because it is simple and every program can read it. That simplicity is also the problem. A CSV carries no information about types, so the program that opens it has to guess whether 0041 is a number, whether 1/2 is a date and whether 1,5 is one and a half or two values. Excel guesses aggressively and silently, and the changes are saved if you press Save. Scientists famously had to rename human genes like SEPT2 and MARCH1 because Excel kept turning them into dates. Converting with a tool that does not guess avoids the whole class of problems. A few tips for clean results. Keep numbers in a CSV without thousand separators and with a dot as the decimal mark, the way most programs export them; values such as 1.234,50 are kept as text so nothing is misread, and Excel can convert them afterwards with Data, Text to Columns. If you receive monthly exports, convert them together into one workbook with a sheet per month, then compare or summarise across sheets. For files that have to go back to the system they came from, keep the original CSV, because saving from Excel to CSV can change dates and numbers again. To turn a workbook back into CSV safely, use Excel to CSV Converter, and if the CSV holds contacts that should go onto a phone, CSV to vCard Converter converts them to a .vcf directly.