Excel (XLS) to Excel (XLSX) Converter
Free, private and instant. Your files stay on your device.
How to convert Excel (XLS) to Excel (XLSX)
- Choose or drop your Excel (XLS) files.
- Click Convert.
- Download your Excel (XLSX) files.
Why convert Excel (XLS) to Excel (XLSX)?
XLSX opens in Excel, Google Sheets and Numbers and keeps columns, sheets and number formats.
About the formats
Excel (XLS). XLS is the older binary Excel format used before 2007. Newer tools and web apps prefer XLSX.
Excel (XLSX). XLSX is the Microsoft Excel workbook format with sheets, formulas and formatting.
Private by design
Most online converters upload your files to a remote server. LocalConvert does the work in your browser, so photos, contracts and spreadsheets never leave your device. There is nothing to install and it works on Windows, Mac, Android and iPhone.
Frequently asked questions
Is this Excel (XLS) to Excel (XLSX) converter free?
Yes. There are no sign-ups, watermarks or daily limits. Convert as many files as you like.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using your own device, so your files never leave your computer or phone. That also makes it fast, and it works for private documents.
Is there a file size limit?
There is no fixed limit. The practical limit is your device memory. Files up to a few hundred megabytes usually work fine on a modern laptop.