OpenAnyFile
Works
Viewing, inspecting and verifying. You get From, To, Subject, Date and the message body, with the attachment list broken out. File details, exact byte size and the detected signature are always shown.
How to open a .msg file
The short version: MSG is an Outlook Message from Microsoft. The longer version — including the quirk that trips most people up — is below, along with a viewer that runs entirely on your own device.
What is a .msg file?
Outlook Message is an email & contact format developed by Microsoft, first appearing in 1997. It is normally produced by Microsoft Outlook.
OLE2 rather than RFC 5322, so it carries Outlook-only properties like categories and flags that are lost when converting to EML.
| Full name | Outlook Message |
|---|---|
| File category | Email & contacts |
| MIME type | application/vnd.ms-outlook |
| Magic bytes (file signature) | D0 CF 11 E0 A1 B1 1A E1 |
| Developer | Microsoft |
| Introduced | 1997 |
| Usually created by | Microsoft Outlook |
| OpenAnyFile engine | RFC 5322 mail parser |
| Opens without upload | Yes — parsed locally in your browser |
Open a .msg file in your browser
OpenAnyFile routes .msg to its RFC 5322 mail parser, which parses From, To, Subject, Date and the message body, with the attachment list broken out.
- Open the OpenAnyFile opener in this browser — nothing to download or sign up for.
- Drag your .msg file onto the drop zone, click to browse for it, or paste it with Ctrl+V.
- The extension is detected and the file is handed to the RFC 5322 mail parser.
- Your MSG opens on its own viewer page: From, To, Subject, Date and the message body, with the attachment list broken out.
- Use fullscreen for a closer look, or download the file back out unchanged. No account, no upload, no watermark, no file-size gate.
What you can and cannot do with it here
Does not work
Editing and re-saving. OpenAnyFile is a reader, not an editor — for changes you still need Outlook or an equivalent.
Local-only by design, not by promise
Plenty of sites promise they delete your uploads. OpenAnyFile avoids the promise by avoiding the upload. When you drop a .msg file in, the browser grants the page temporary read access to those bytes and nothing more — the page has no path to send them anywhere. You can verify it in seconds: open DevTools, switch to the network tab, and open a file. The request list stays empty.
Frequently asked questions about MSG files
Can I open a .msg file without installing Outlook?
Yes. OpenAnyFile's RFC 5322 mail parser runs in your browser, so you can read a MSG file with nothing installed. You get From, To, Subject, Date and the message body, with the attachment list broken out. For full editing you still need the original application — this is a viewer, not an editor.
How can I check a file really is a MSG file?
Look at the first bytes rather than the extension. A genuine MSG begins with D0 CF 11 E0 A1 B1 1A E1. Opening the file in OpenAnyFile shows that signature in the file-details panel, so a file renamed to .msg by mistake is easy to spot.
Is it safe to open a MSG file online?
With OpenAnyFile, yes, because nothing is uploaded. The file is read locally through your browser's File API and never leaves your device, so there is no server copy to leak, log or retain. That matters most for the kind of file people are least willing to hand to a random converter site.
What is a .msg file, exactly?
Outlook Message — an application/vnd.ms-outlook format created by Microsoft since 1997. OLE2 rather than RFC 5322, so it carries Outlook-only properties like categories and flags that are lost when converting to EML.
Does the same viewer handle formats related to MSG?
Yes — the same engine also opens .eml, .mbox, .ics, so you can compare related files without switching tools.
Related formats
These open with the same engine, so if you have one of these sitting next to your .msg file, it will open too: