Online winmail.dat Reader

Read the message and preview hidden Outlook attachments in your browser - your file is never uploaded.

Drop your winmail.dat file here

or click to choose a file - it never leaves your browser

100% Private

The decoder runs as WebAssembly inside your browser. Your file and its contents never leave your device.

No Signup, No Limits

Decode as many winmail.dat files as you like, free. No account, no email address, no watermarks.

Same Engine as the App

This page uses the exact same decoding engine as Winmail File Viewer for iPhone, iPad, and Mac.

Get Winmail.dat Files on Your iPhone?

Open them straight from the Mail share sheet with Winmail File Viewer - offline and on-device.

Download Winmail File Viewer

Free to try • Works offline • On-device processing

Winmail.dat Reader Online FAQ

Can I use this as a winmail.dat reader online?

Yes. The online decoder can read the message preview from a winmail.dat file and show the hidden Outlook attachments inside it.

Does the online reader upload my file?

No. Decoding runs in your browser with WebAssembly, so the winmail.dat file stays on your device.

Can it extract winmail.dat attachments?

The page previews the files inside winmail.dat and shows attachment names, types, sizes, and image thumbnails when available. Use the app when you need to save and share the extracted attachments.