EML and MSG Viewer, and EML to PDF
The ProofSnap EML and MSG Viewer, last updated in October 2026, opens .eml files and Outlook .msg files in your browser without Outlook. Read the message, read every header and check each attachment's SHA-256 hash, then save the email as a PDF with the full headers. Nothing is uploaded; the file never leaves your device.
Open an email file
Runs entirely in your browser. Nothing is uploaded; you can check this in your browser's Network tab.
Drop an .eml or .msg file here
or use Choose file below. Files over 25 MB still open, but slowly.
Message
Loading them contacts the servers that host them, which can tell the sender that the message was opened, when, and from which IP address.
The body is cleaned with DOMPurify and shown in a sandboxed frame: no scripts, no forms, links do not open.
Attachments
This message has no attachments.
| Name | MIME type | Size | SHA-256 | Download |
|---|
Source file
Need it sealed for a dispute? We turn the thread into a numbered transcript with the full headers, hashed attachments and an eIDAS qualified timestamp, delivered in 48 hours.
How to save an email as an .eml or .msg file
The viewer needs the message file itself. Every mail app can save one; this is the path in each, one file per message.
In Gmail
Gmail, one message at a time or all at once
- 1Open the message and click the three dots at its top right.
- 2Choose Download message. You get an .eml file with the headers and every attachment inside.
- 3For a whole thread, select the messages in the list, then More, Forward as attachment, and send them to yourself. Each travels inside the new message as a copy, headers included.
For a very long thread you can also apply a dedicated label to it and export just that label in Google Takeout, which gives you one .mbox file. An .mbox file keeps the headers just like an .eml.
In Outlook
Outlook, on the desktop and on the web
- 1Classic Outlook on Windows: select the messages in the thread with Ctrl and drag them straight into an empty folder on your desktop. Each is saved as a .msg file with its attachments. Selecting them and pressing Ctrl + Alt + F forwards them all as attachments instead.
- 2New Outlook: open the message, click More actions (the three dots) and choose Save as. In Outlook on the web choose Download, then Download as EML. Both give an .eml file.
- 3Whatever the route, do not choose Print or Save as PDF. Those outputs keep no headers.
Both .msg and .eml keep the full headers and the attachments. Open one file afterwards in our free EML and MSG Viewer to check that the headers are really there. To export a whole folder from classic Outlook, use File, Open & Export, Import/Export, Export to a file, Outlook Data File (.pst), the format e-discovery tools expect.
Thunderbird and Apple Mail
Thunderbird: select the messages, right-click and choose Save As. Each is written out as an .eml file. Dragging the selection into a folder does the same thing.
Apple Mail: select the messages and drag them from the message list into a folder in Finder. You get one .eml per message, attachments included.
The one mistake that costs you the evidence
Forward (the normal one): a new message is created, the original headers become body text, and the DKIM signature no longer covers them.
Forward as attachment: a copy of the original message, headers included, travels inside the new message, so it stays usable.
Saved files: the safest route.
Message size limits stop large threads from being forwarded. If the thread is larger than roughly 20 MB, save the files instead.
Saved the files? Send them to us and get a certified thread within 48 hours.
How to open an .eml or .msg file without Outlook
An .eml file is a plain MIME message, the format Gmail, Thunderbird, Apple Mail and Outlook on the web give you when you download a message. An .msg file is what classic Outlook for Windows writes when you drag a message to the desktop or a File Explorer folder, or use File > Save As. The viewer reads both without any mail program installed.
- Drop the .eml or .msg file onto the viewer above, or click Choose file and pick it from your computer.
- Read the message card: subject, sender, recipients, date and Message-ID, all taken from the file itself.
- Switch between the HTML, Plain text and Full headers tabs to see the formatted message, its text version and every header line in its original order.
- Download any attachment from the table and compare its SHA-256 hash with the copy you hold elsewhere.
How to save an email as PDF with the full headers
Printing from Gmail or Outlook keeps the visible text and drops the routing headers. The report this viewer prints puts them back on paper, together with the fingerprint of the file you printed from.
- With the message open, click Save as PDF. Your browser opens its print dialog with a report layout: the source file and its SHA-256 hash, the full header block, the message card, the body and the attachment table.
- Choose Save as PDF (on Windows also Microsoft Print to PDF) as the destination and pick A4 or Letter.
- Save the PDF and store it in the same folder as the original email file.
- Keep both. The PDF is the reading copy; the original file is the one that can be checked.
Why a PDF alone is a weak copy of an email
A PDF is only a picture of a message. Its text can be edited before printing, and nothing in it ties it back to the mail server that delivered the original. The original file is different: its headers record each server the message passed through, and many messages carry a DKIM signature that can be checked against the key the sending domain publishes, as long as it still publishes that key.
So keep three things together: the original .eml or .msg file, its SHA-256 hash as printed in the report, and the PDF as the reading copy. If the hash of the file you hand over later matches the hash in the report, the file has not changed since you made the report.
Headers show the route a message took and, through DKIM, whether the signed parts changed after sending. They do not show who sat at the keyboard. A .msg file usually keeps the transport headers but not the original MIME bytes, so its DKIM body hash cannot be recomputed from it. Where you can, save the same message as .eml as well.
Are the attachments safe to open?
The viewer never opens or runs an attachment. It reads each one as raw bytes, computes its SHA-256 hash and offers it as a download, nothing more. The message body is cleaned with DOMPurify and shown in a sandboxed frame where scripts, forms and plugins cannot run. Once you download an attachment, it is an ordinary file on your computer: scan it with your antivirus before you open it, especially Office documents, archives and anything executable.
Need the whole thread certified for a dispute?
Send us the saved .eml or .msg files and within 48 hours you receive a certified thread: a numbered transcript with the full headers, every attachment hashed, and an eIDAS qualified timestamp. From $59.99.
Doing it yourself? Read the guide: Can emails be used as evidence in court?
Frequently asked questions
How do I open an .eml file without Outlook?
Drop it onto the EML and MSG Viewer on this page. It reads the file in your browser and shows the subject, sender, recipients, date, body, every header and every attachment. No mail program and no account are needed.
How do I open an .msg file without Outlook?
Drop the .msg file onto the same viewer. It reads the Outlook file format directly and shows the message, the transport headers when Outlook stored them, and the attachments. If the formatted body exists only as compressed RTF, the viewer shows the plain text version and tells you so.
How do I convert an email to PDF with headers?
Open the file in the viewer and click Save as PDF, then choose Save as PDF as the destination in the print dialog. The PDF contains the full header block, the message, the attachment list with SHA-256 hashes and the hash of the source file.
Are the attachments safe to open?
The viewer never opens or runs them. It only hashes them and offers a download. A downloaded attachment is an ordinary file on your computer, so scan it with your antivirus before you open it.
Why don't remote images load?
Images hosted on remote servers are blocked by default, because loading them tells the sender that the message was opened, when, and from which IP address. Images stored inside the email still show. Turn on Show remote images only if you accept that your browser contacts those servers.
What is the SHA-256 hash for?
It is a fingerprint of the file. Change a single byte and the hash changes completely. Keep the PDF report, and anyone can later recompute the hash of the email file to confirm it is the same file you viewed.
Does a PDF of an email prove it is authentic?
No. A PDF only shows what a message looked like, and its text can be edited before printing. Keep the original .eml or .msg file and its SHA-256 hash with the PDF, because the original still carries the headers and signatures that can be checked.
Is my email uploaded?
No. The file is read and processed entirely in your browser. It is not sent to ProofSnap or to anyone else, and you can confirm this in the Network tab of your browser's developer tools while you open a file.
Numbered transcript, full headers, every attachment hashed, eIDAS qualified timestamp. Delivered in 48 hours.
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Disclaimer: This page is general information, not legal advice. Evidence rules differ between courts and jurisdictions, so ask a qualified lawyer about your case.