Turn CSV, TSV or TXT files into a clean .xlsx workbook with the separator, encoding and column types sorted out first — all in your browser, nothing uploaded.
CSV to Excel Converter
Turn CSV, TSV or TXT files into a clean .xlsx workbook with the separator, encoding and column types sorted out first — all in your browser, nothing uploaded.
Your CSV files are read and converted on your device. Nothing is uploaded to ArrayKit, so exports with customer or financial data stay with you.
The CSV to Excel Converter turns one or many CSV, TSV or TXT files into a real .xlsx workbook without the damage a double-click does. It works out the separator (comma, semicolon, tab or pipe), the quoting and the text encoding, including UTF-16 and Windows-1252 exports, then checks every column before deciding what its cells should be. A column becomes numeric only when every value is an unambiguous number, so ZIP codes with leading zeros, 16-digit IDs and phone numbers with a plus sign stay as text instead of turning into 2134 or 1.23E+15. Decimal commas, dates such as 05/03/2024 and TRUE/FALSE values are recognised, and any column can be overridden from the preview. Several files can share one workbook with a sheet each, or come out as a zip of separate files. Everything is converted on your device.
Features
Detects comma, semicolon, tab and pipe separators, quoting, BOMs and line endings
Reads UTF-8, UTF-16 and Windows-1252 files so accents survive
Keeps leading zeros, 16-digit IDs and phone numbers as text instead of mangling them
Recognises decimal commas, thousands separators, ISO dates, day-first and month-first dates
Per-column override to force text, number, date or TRUE/FALSE before you download
Combines several files into one workbook with a named sheet each, or a zip of workbooks
Separator: semicolon · decimal comma · dates read day first
name text
zip text (02134 keeps its zero)
price number (1250.5, 980)
joined date (2024-03-05, 2024-03-25)
The semicolon file is split correctly, the comma decimals become real numbers, and the ZIP code stays 02134.
Common errors & troubleshooting
Zip codes or IDs still lose their leading zeros after opening the file. — Open the .xlsx this tool writes rather than the original CSV. If a column was read as numbers, switch it to Treat as text in the menu under its heading and convert again.
Everything lands in one column. — The separator was guessed wrong. Pick comma, semicolon, tab or pipe in the Separator list instead of Detect automatically, and the preview will split the columns immediately.
Accented letters turn into odd symbols. — The file was saved in an older encoding. The converter reads UTF-8, UTF-16 and Windows-1252 automatically, so use the .xlsx output, or the CSV for Excel option, which writes UTF-8 with a byte-order mark.
Dates come out with the day and month swapped. — Values like 05/03/2024 can be read either way. Change Dates like 05/03/2024 to Day first or Month first, and the preview and the download both follow.
Frequently asked questions
How does the CSV to Excel Converter keep leading zeros in ZIP codes?
It reads every value in a column before choosing a type. If any value has a leading zero, more than 15 digits or a phone-style plus sign, the whole column stays text, and those cells also carry the Text format so retyping a code in Excel keeps its zero.
Can I combine several CSV files into one Excel workbook?
Yes. Drop all the files together and pick One workbook. Each file becomes its own sheet named after the file, with characters Excel forbids removed, names shortened to 31 characters and duplicates numbered. Choose Zip of files for separate workbooks instead.
Does the converter handle semicolon files from European Excel?
Yes. Semicolon-separated files with decimal commas, such as 1.234,56, are detected from the data itself. You can also set the separator and the decimal mark by hand if a file is unusual.
Which text encodings does the CSV to Excel Converter read?
UTF-8 with or without a byte-order mark, UTF-16 in either byte order, and Windows-1252, which is what many older Excel exports use. The encoding is shown above the preview.
How large a CSV file can I convert to Excel here?
The limit is your device's memory rather than an upload cap. A sheet can hold 1,048,576 rows, and the tool tells you before download if a file is over that. Very large files convert more smoothly as CSV for Excel or split into parts.
Do the header bold, frozen row and filters work in the older .xls format?
The header styling is written to .xlsx files. The older .xls format keeps the sheets, column widths and typed cells but not the styled header, and it is limited to 65,536 rows and 256 columns.
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