Free online MSG to EML converter

Some mail clients, help-desk systems, and archive tools accept .eml but cannot open Outlook’s .msg files. Converting the message makes it easier to share, import, or archive while retaining standard email headers, body content, and usually attachments.

What the MSG format is

MSG is Microsoft Outlook’s proprietary file format for an individual email, calendar item, contact, task, or meeting request. Outlook creates an MSG file when you use File → Save As and select Outlook Message Format (*.msg), or drag an Outlook item to a Windows folder.

An MSG file uses Microsoft’s Compound File Binary Format and stores MAPI properties such as sender, recipients, subject, timestamps, message body, attachment data, and Outlook-specific metadata. MSG files commonly occur in Outlook exports, support-ticket folders, legal-discovery collections, and email evidence copied from Windows systems.

What the EML format is

EML is a MIME email file containing Internet-style headers, a plain-text or HTML body, and MIME parts for attachments and alternative body formats. The format is supported by Mozilla Thunderbird, Apple Mail, Windows Mail, many mail-server utilities, and numerous document-management and e-discovery systems.

EML is useful when the destination expects a standard RFC 5322-style message, when email must move between different mail platforms, or when a portable individual-message file is needed. Its container is generally readable text, but HTML content and binary attachments remain MIME-encoded and may appear as encoded data in a text editor.

Convert with 101convert

1. Open the MSG-to-EML converter on 101convert.com.
2. Select one or more .msg files.
3. Start the conversion and wait for processing to finish.
4. Download the resulting .eml file or output archive when provided.
5. Open the output in the mail client or import utility that will use it.
6. Check the sender, recipients, subject, date, body formatting, attachment count, attachment names, and inline images.

This option runs without an installed mail client and is suitable for occasional conversions. Do not upload confidential, regulated, privileged, or legally restricted messages unless your organization’s data-handling policy permits processing by the service.

Convert locally with msgconvert

The Perl-based msgconvert utility can convert many standard Outlook MSG files without Outlook. Install it through the package manager or Perl distribution available for your operating system; package names and installation steps differ between Linux, macOS, and Windows environments.

In a terminal, change to the directory containing the source file and run:

msgconvert message.msg

The utility normally writes an EML file beside the source using the same base name. For multiple files in a Unix-compatible shell, run:

for f in *.msg; do msgconvert "$f"; done

Test representative messages before batch-processing an archive. A local converter is preferable for restricted data, but its support for unusual Outlook properties depends on the source file and the installed utility version.

Compatibility limitations

Normal headers, plain-text or HTML content, inline images, and ordinary file attachments can usually be transferred. MSG properties with no MIME equivalent may be omitted or flattened, including Outlook categories, follow-up flags, voting buttons, custom forms, Exchange-specific metadata, and some meeting or contact fields.

Inspect messages containing RTF bodies, embedded Outlook objects, protected content, S/MIME encryption, digital signatures, or very large attachments separately. RTF conversion can change formatting; embedded objects may become ordinary attachments or be lost; and conversion can invalidate a digital signature. Encrypted content may remain inaccessible unless Outlook or the original mail system can decrypt it.

Keep the original MSG files as authoritative copies for legal, compliance, or evidence archives. Verify the converted EML in the application that will ultimately import it because mail clients differ in MIME parsing, HTML rendering, character-set handling, and attachment treatment.