Think CONVERT Files stay on this device
Never uploadedSpreadsheets, contacts, documents and routes are converted inside your browser. We never see them.
Free, with no limitsNo account, no daily limit, no file-size cap. As many files as you like.
Works on phones, and offlineiPhone, Android and computers, even without a connection once loaded.

How to use XLS to XLSX

  1. Open your old .xls files. Add as many as you like.

  2. Press Convert.

  3. Save the new .xlsx files, or a ZIP of them all.

Questions

Why convert XLS to XLSX?

XLSX files are smaller, open without Compatibility Mode, can't carry old-style macros and work best with Google Sheets, Numbers and newer Excel.

Are formulas and sheets kept?

Yes. Every sheet, value and formula is carried across. Some old formatting, such as unusual colours, may look slightly different.

Are my files uploaded?

No. Everything happens inside your browser, on your own device. The site's security settings stop the page from sending your files anywhere.

Is it free?

Yes. No sign-up, no daily limit and no watermark.

Does it work on iPhone and Android?

Yes, in Safari, Chrome and other modern browsers. You can open files from the Files app or your downloads, and save the results back.

Know someone who'd find this handy?

Send the link to a friend or colleague. It's free for them too, with no sign-up.

Other converters upload your files. This one can't.

Customer lists, contacts, bank exports and the routes you run from home stay on your phone or computer from start to finish.

How it stays private
  1. 1You open a file. It loads into your browser only.
  2. 2The conversion happens on your device.
  3. 3You save the result. Nothing was sent anywhere.

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