Open winmail.dat files privately
Extract Outlook attachments without uploading them or installing Outlook.
Drop your winmail.dat here
or choose it from your device
TNEF / winmail.dat · up to 25 MB · 100 attachments
Parsing and ZIP creation happen inside this browser tab. The file is not uploaded, logged, or stored.
attachments found
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A small tool for a strangely persistent file
winmail.dat is a TNEF package. Microsoft Outlook sometimes wraps ordinary attachments in its Transport Neutral Encapsulation Format. Other mail apps may show only the wrapper instead of the files inside it.
Drop that wrapper into the viewer. Your browser reads its attachment records, shows the safe filenames and file types, then lets you download one file or a ZIP of everything. Outlook is not required.
Your mail stays yours
There is no upload endpoint behind this page. Parsing, attachment downloads, and ZIP creation happen locally in this browser tab. We do not add analytics, ads, remote fonts, error reporting, or storage that records filenames or file contents.
Useful details
Does the file really stay on my device?
Yes. The viewer has no file-upload code or server API. The selected bytes remain in this tab's memory until you close it or choose another file.
What can I extract?
The MVP lists and downloads attachments found inside valid TNEF files. It intentionally does not display unverified email bodies, headers, or remote images.
Can it open MSG or EML files?
Not yet. This first release is deliberately limited to winmail.dat. MSG and EML need separate privacy-safe rendering rules and will be considered as future tools.
Why was my file rejected?
It may not be TNEF, may have been truncated by email software, may contain no attachments, or may exceed the 25 MB / 100 attachment safety limits.