ViewCSV
Create a real .xlsx workbook from CSV, TSV or delimited text. Open or paste the data, check how it splits into columns, choose the worksheet settings and download XLSX. Conversion happens in this browser tab; no Excel installation or file upload is required.
Turn CSV rows into an XLSX worksheet
- Open the CSV or paste its contents. Inspect the input table before exporting.
- If the columns do not line up, choose the delimiter in Import settings. If characters look wrong, choose the source encoding.
- Name the worksheet and choose whether values stay text or numbers and true/false may be detected. Bold headers, a frozen first row and fitted column widths are available.
- Select Download XLSX. The result is one workbook containing one worksheet.
Changing .csv to .xlsx is not a conversion
CSV is delimited text. XLSX stores cells, value types and worksheet layout in a workbook structure. Renaming the source file cannot create that structure; this tool writes a new workbook.
The output is .xlsx, not legacy .xls or macro-enabled .xlsm. It can be opened as a workbook in Excel or imported into another application that supports XLSX, such as LibreOffice Calc or Google Sheets.
Choose cell types before downloading
Text is the default: codes such as 00123, long identifiers and dates stay as written. Formula-like strings are not turned into executable formulas.
Number detection works conservatively by column, with an additional XLSX precision check. Values beyond 15 significant digits stay text. Decimal-comma values and mixed text columns are not silently converted; blanks become empty cells. For detailed Excel import advice, see CSV to Excel.
Several CSV files, one workbook
Use Batch CSV to Excel to put files on separate sheets, append them into one sheet, or mix merged groups with separate sheets. This single-file converter keeps the worksheet formatting controls close at hand.
Inputs must fit 25 MiB, 100,000 rows, 250 columns and 2 million cells. A cell longer than 32,767 characters stops XLSX export rather than being cut off. To extract a sheet from a workbook later, use Excel to CSV.
Example: a quoted comma stays in one cell
This synthetic inventory sample has two data rows and three columns. With the default text setting, both SKU values and quantities are text cells. With number detection, qty becomes numeric while the leading zeros in sku remain intact. The comma in Cable, USB stays inside the note cell.
sku,qty,note 00123,12,"Cable, USB" 00124,7,Adapter
sku | qty | note 00123 | 12 | Cable, USB 00124 | 7 | Adapter
Questions and answers
No. The browser creates the XLSX download. You only need a compatible spreadsheet application when you want to open and work on the downloaded workbook.
No. CSV has no workbook formatting to recover. You can set the header and column layout offered here, while formula-like source values remain data.