spreadsheet / file
CSV to XLSX Converter
Wrap flat CSV data into an XLSX workbook for spreadsheet workflows.
CSV to XLSX adds workbook structure, but it does not invent formulas or styling that was not present in the source.
Upload CSV
Supported input: csv. Max file size: 100 MB.
Downloads stay available for 1 day on your current access level.
Ready files get a temporary download link that you can open or share.
Convert multiple files
If you repeat the same format change often, you can prepare a batch and process several files together.
Batch conversion is available on the Pro plan. Sign in to upload up to 25 files at once for this converter.
Step by step
How to use this converter
- 1
Choose a CSV file
Start with a supported CSV source and check that the file is the version you want to convert.
- 2
Review the format notes
CSV to XLSX Converter explains what is preserved, what can change, and which settings matter before upload.
- 3
Upload CSV
Upload the source file, run the conversion, and download the finished XLSX result from the temporary link.
- 4
Keep the original
Save your original CSV file until you have checked that the XLSX output fits the next app or publishing flow.
Expected output
You receive a XLSX file that matches the stated converter limits. Good when downstream editing needs an actual spreadsheet container.
Before you convert
Common issues to check
- - delimiter detection should be explicit
- - large CSV files need quotas and streaming
- - semantic typing without explicit parsing rules
- - original encoding quirks
Not ideal for
- - delimiter detection should be explicit
- - large CSV files need quotas and streaming
- - semantic typing without explicit parsing rules
- - original encoding quirks
Before you start
You should know the result and the limits before the upload begins.
What stays
- - cell values
- - row ordering
- - basic columns
What may change
- - semantic typing without explicit parsing rules
- - original encoding quirks
Known limitations
- - delimiter detection should be explicit
- - large CSV files need quotas and streaming
Typical use cases
- - open CSV in Excel
- - send structured data to non-technical users
- - prep a workbook for review
Available options
- - delimiter
- - encoding
- - header row mode
FAQ
What happens during CSV to XLSX conversion?
The converter places flat CSV rows into an XLSX workbook so the data is easier to edit in spreadsheet software.
Are uploaded files kept permanently?
No. Files are kept only for a short time and downloads are served through temporary links.
Can quality or formatting change?
Yes. Each converter page calls out what is preserved, what may be lost, and which settings matter before upload.
Related converters
Guides and comparisons
CSV vs TSV: which delimiter is safer for your data?
CSV is more common, while TSV is often safer when values already contain commas and you need flatter parsing.
XLSX vs CSV: when do you need a workbook and when do you need plain text?
Choose XLSX for workbook structure, multiple sheets, and editing context. Choose CSV for flat imports and lightweight data handoff.