CSV to Excel Converter
Convert CSV data to downloadable .xlsx files — with live table preview
How to Use the CSV to Excel Converter
- Paste CSV data (comma-separated).
- Optionally set a sheet name.
- Click Download Excel to get an .xlsx file.
Powered by SheetJS. All processing is local.
What is CSV to Excel Conversion?
The CSV to Excel Converter converts raw Comma-Separated Values (CSV) or TSV files into formatted Microsoft Excel (.xlsx) workbooks. It preserves text encoding (including UTF-8 with BOM), prevents truncation of leading zeroes in IDs and zip codes, and creates native binary Excel spreadsheets ready for financial and business analysis.
Common Uses
- Fixing CSV import glitches in Excel (such as leading zeroes being stripped from phone numbers)
- Converting CSV database exports into structured workbooks for non-technical stakeholders
- Combining comma and semicolon-delimited international data files into standardized XLSX files
- Formatting raw log data and transaction records for immediate spreadsheet review
Frequently Asked Questions
Why does Excel often open CSV files with corrupted accents or characters?
Excel often assumes legacy ANSI encoding for CSVs unless a UTF-8 BOM header is present. By converting directly to a native `.xlsx` workbook, UTF-8 character encoding is strictly preserved.
Does this tool preserve leading zeroes in numbers?
Yes. Our conversion pipeline detects strings such as product SKUs, postal codes, and bank account numbers, preserving them as textual cell values rather than truncating them.
Are there row limits on the conversion?
The tool uses SheetJS running locally in Web Workers, easily converting files with tens of thousands of rows within seconds right in your browser.
Notes from this implementation
A workbook, not a prettier CSV
The page builds a spreadsheet file from the rows, so a spreadsheet application opens it as cells. That is different from renaming a .csv to .xlsx, which does not change the contents. Formulas are not invented. A cell that starts with = may be interpreted as a formula by the application that opens the file. If your data contains =, +, or @ at the start of a cell, prefix it or the sheet will evaluate it. That is a property of spreadsheets, and it matters when the CSV came from untrusted text.
Dates that look like dates may be converted to date serials on open. If the column is an identifier that happens to look like a date, format it as text in the source. The conversion runs locally from the text you paste or the file you drop.