Open MSG files without Outlook
The .msg format is Outlook-only by design — a Microsoft Compound File container that macOS, Linux, iOS and Android have no native reader for. When a .msg arrives on a machine without Outlook, the usual advice is "install Outlook" or "forward it to someone who has it", both of which are wrong answers when the message is confidential.
This viewer reads the compound file structure directly in your browser: sender name and address, the full recipient list, sent date, subject, message body and the attachment inventory. It works on any OS, requires no installation or signup, and — unlike .msg viewer apps of unknown provenance — never transmits the file anywhere.
If you need the message as a document, convert it to PDF in the same tool: full header block, body and attachment manifest, generated locally.
Open the converter — free, no upload
Questions
Why won't my Mac open a .msg file?
Apple Mail reads .eml (a standard format) but not .msg (Microsoft's proprietary container). You either need Outlook for Mac, or a parser like this one that reads the container format itself.
Can I extract attachments from the .msg?
The viewer lists them; the converter's full version extracts the original attachment files into a ZIP alongside the PDF.
Are .msg and .eml the same thing?
No. .eml is the open internet format (plain text MIME). .msg is a binary Microsoft container. They hold the same kind of content, which is why both convert to identical PDFs here.