Clean — by Similarity API
Free Excel to CSV Converter — XLSX & XLS
Convert Excel to CSV without uploading your file. Open XLSX or XLS, choose a worksheet and download UTF-8 CSV with your preferred separator.
Open an Excel workbook
Drop a file or choose from your device
Your data never leaves your browser
How it works
Three steps. One clean result.
Step 1
Open your workbook
Choose an XLSX or XLS file from your device.
Step 2
Pick a worksheet
Preview one sheet and choose the output separator and header options.
Step 3
Download CSV
Save a UTF-8 CSV ready for import into spreadsheets or other tools.
Why Clean
The details that make a difference
Pick the right sheet
CSV holds one table. Select the worksheet you actually want to export.
Accents and identifiers
UTF-8 retains international text; displayed leading-zero formats are used when available.
Values, not a workbook
CSV does not store styling, charts, macros or formulas. Cached formula results are used.
Before
Worksheet: Contacts ID Name 0012 Ana García
After
ID,Name 0012,Ana García
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Frequently asked questions
Is this tool free?
Yes. Clean is free, with no account, payment or download gate.
Is my data uploaded?
No. Processing happens in your browser. Your input is not sent to our servers, sold, shared or used for AI training. Large inputs are limited by your device’s available memory.
Can I convert XLSX and XLS?
Yes. Both modern XLSX and older XLS workbooks are supported. Encrypted or password-protected workbooks are not supported.
Can I export every worksheet?
Choose and download each sheet separately. Each CSV contains one worksheet; it cannot contain multiple tabs.
What happens to formulas?
Saved formula results are exported when present. This tool does not recalculate formulas; missing cached results can appear blank.
Will leading zeros survive?
The converter reads displayed cell text, including leading-zero number formats where saved. A spreadsheet opening the CSV may still infer numbers; import identifiers as text to retain zeros.