How to open a winmail.dat file
- Save winmail.dat from your mail app. On an iPhone: press and hold it, then Save to Files.
- Drop it into the box above, or choose it from your device.
- The free preview lists every file inside, with its name and size.
- Download each file, or all of them in one zip: free from one email up to 2 MB, or unlock with a pass.
What is winmail.dat?
When Outlook sends an email in its Rich Text format, it can wrap the attachments, and sometimes the formatted message, into one file called winmail.dat. Outlook can unwrap it, but Apple Mail, iPhone, Android, Gmail and most other apps can't, so you see winmail.dat instead of the PDF or spreadsheet that was sent.
Nothing is wrong with the file, and it isn't a virus by itself. It is simply packed in Microsoft's own format, called TNEF. This opener unpacks it in your browser and gives you back each file with its original name and type.
Why you got a winmail.dat fileHow to save winmail.dat from your mail app
iPhone and iPad
In Mail, press and hold winmail.dat, then choose Save to Files. Tap the box above and pick it.
Gmail
Point at the attachment and click the download arrow.
Mac Mail
Drag winmail.dat from the email onto the box above.
Android
Download the attachment, then pick it from Downloads.
Outlook.com
Download the attachment from the message, then drop it above.
How to stop getting winmail.dat files
Ask the sender to send in HTML instead of Rich Text. In Outlook for Windows, that is File, Options, Mail, then Compose messages in this format: HTML. Under Message format on the same page, they can also set Rich Text emails to internet addresses to convert to HTML.
Get the files on your phone
Opened winmail.dat on a computer but need the files on your phone? After unlocking, scan the QR code next to the download button. The files are encrypted before they leave your computer and open in your phone's browser, ready to save or share. The link expires after 24 hours.
Is it safe to open confidential emails?
Yes. Emails often hold contracts, invoices and personal details, so this tool works inside your browser. The file is opened on your own device, and we never see it. Scripts in an email are removed and it is shown in a sealed frame, so a harmful email cannot run code on your computer.
Questions about winmail.dat
Is winmail.dat a virus?
No. It's a normal Outlook file that packs the attachments. Any file inside it could still carry a virus, as with any attachment, so only open files from people you trust.
Do you see my files?
No. The file is opened in your browser, so we never see your email or its attachments.
Why is my winmail.dat empty?
Sometimes it holds only the formatting of the message, with no attachments. The preview tells you what is inside before you pay.
Can I open it on an iPhone?
Yes. Save it to Files from Mail, then open this page in Safari and tap the box above.
Can I read the message text too?
Yes. If the winmail.dat holds the formatted message, it is shown alongside the files.
Does it work with Gmail?
Yes. Gmail shows winmail.dat as an attachment it can't preview. Download it, then drop it above.
Do the files keep their names?
Yes. Each file comes back with its original name and type, so it opens in the right app.
What does it cost?
One email up to 2 MB is free, every time. Bigger emails are $1.99 each, after a free preview (up to 3 previews a day on each device). A 24-hour pass is $6.99 for unlimited emails and batch. Pro is $12.99 a month, or $89 a year. The one-time passes never renew.