Email File Viewer

How to open an email file

1. Drop the file onto the box above, or click to choose it. You can pick several files and switch between them.
2. A single message opens straight away. A mailbox or Outlook data file shows a message list first; click a message to open it.
3. Read the message, then download one attachment or all of them as a single .zip.

What each file type is, and why you have one

.eml — one saved message

The plain, standard format for a single email. You get one when you drag a message out of Thunderbird or Apple Mail, use “download message” in a webmail service, or receive a forwarded message as an attachment. More about EML files.

.msg — one message saved from Outlook

Outlook for Windows has its own format for a saved message. It only opens in Outlook, which is a problem on a Mac, a Chromebook, a phone or a PC without Office. More about MSG files.

winmail.dat — the attachment you did not ask for

When someone sends Outlook “rich text” mail to a non-Outlook address, the formatting and the real attachments arrive packed into one file called winmail.dat. The files you were meant to get are inside it. More about winmail.dat.

.mbox — a whole mailbox in one file

Many messages stored one after another. Google Takeout gives you your Gmail this way, and Thunderbird keeps each folder as one. These files are often several gigabytes. More about MBOX files.

.pst and .ost — Outlook data files

Outlook’s own archive of mail, folders, calendar and contacts. People end up with one after leaving a job, switching away from Outlook, or receiving an export from an IT department. More about PST files.

What is supported

• Subject, sender, recipients, date, plain-text body and HTML body, plus the raw headers when the file has them.
• Attachments with their original names, including inline images, calendar invites (.ics) and messages attached to messages, which open as messages in their own right. A winmail.dat attached to an .eml opens directly too.
• Older and non-English mail: quoted-printable and base64 parts, encoded header words, and legacy character sets such as ISO-2022-JP, Windows-1252, GBK and KOI8-R.
• Outlook messages whose body exists only as compressed rich text: the HTML or plain text is recovered from it.
• “Save message as .eml” for Outlook messages, Outlook data-file messages and mailbox messages, so you can move them into another mail program.

What is not supported

• Encrypted mail (S/MIME or PGP) is not decrypted; the encrypted parts are listed as attachments. Signed mail opens normally and the signature shows as an attachment. Signatures are not verified.
• Remote images are never loaded, and there is no switch to turn them on. Images embedded in the message itself are shown.
• Search covers subject, sender and Gmail labels, not the text of every message body.
• Calendar entries and contacts inside a PST or OST show their title and notes only, not a calendar or address-book view.
• This is a viewer. It does not send, reply, edit or convert whole mailboxes in bulk.

Privacy: why this runs in your browser

Email is about as sensitive as files get: contracts, medical letters, password resets, other people’s addresses. An online viewer that asks you to upload a mailbox is asking for all of it. This one does the work on your device. The file is read by JavaScript in this tab, nothing is sent to a server, and there is no account or tracking.

Opening HTML email carries its own risk, because marketing mail contains tracking pixels that report when and where you opened it. Here the message body is stripped of scripts, forms and remote content, then shown in a locked-down frame that cannot run code or reach the network. Links still work and open in a new tab.

Frequently asked questions

Is my email uploaded anywhere?

No. The file is read and decoded in your browser. Nothing is sent to a server, there is no account, and the page does not use analytics scripts.

Why are images missing from the message?

Images that live on a remote server are blocked on purpose, because loading them tells the sender that you opened the mail. Images that are embedded in the file itself are shown. The notice above the message tells you how many remote items were blocked.

How large a file can I open?

Mailbox and Outlook data files are read in pieces as you browse, not loaded into memory, so size is not the limit: a 2.4 GB mailbox with 600,000 messages was indexed in a few seconds in testing. A single .eml or .msg is read whole, which is fine for any normal message.

Can I get the attachments out without reading the message?

Yes. Every attachment has its own download button, and “Download all as .zip” saves them together with their original file names.

Can it open a message that is attached to another message?

Yes. Attached messages have an Open button. The attached message opens with its own body and attachments, and a Back button returns you to the message it came from.