Free online MBX to TXT converter

What the MBX format is

In the Internet and email context, MBX is a mailbox file format associated primarily with Qualcomm Eudora. An MBX file stores multiple email messages, usually including headers such as From, To, Subject, and Date, followed by each message body; Eudora commonly kept a related .toc table-of-contents file beside it.

MBX files are typically encountered after recovering mail from an old Eudora installation, copying an archived mailbox, or migrating messages from legacy systems. The file is not normally intended to be edited directly, and changing its internal separators or headers can make messages unreadable to mail software.

What the TXT format is

TXT is an unformatted character-based file. It is supported by text editors, command-line tools, indexing systems, scripts, and document-management software without requiring an email client.

A TXT export is useful when you need searchable or editable message content, long-term plain-text archiving, or a smaller file without HTML styling and attachments. TXT does not preserve mailbox folders, read or unread flags, threading, message indexes, embedded images, or attachment files as usable attachments.

How to actually convert MBX to TXT

For a single mailbox, the built-in converter on 101convert.com can perform the conversion without installing software:

1. Make a backup copy of the original .mbx file and keep the copy unchanged.
2. Open the MBX-to-TXT converter on 101convert.com.
3. Upload the mailbox file, choose TXT as the output format, and start the conversion.
4. Download the generated TXT file and open it with a UTF-8-capable editor such as Notepad, Notepad++, or a Unix text editor.

For a local conversion, first try importing the MBX file into a mail client that supports Eudora mailbox import, then export the imported messages as plain text. In Thunderbird, the relevant import capability can depend on the installed version and add-ons; verify that the importer identifies the file as an Eudora mailbox rather than as an ordinary document.

A script can extract a standard mbox-compatible MBX file without uploading it. Save the following as mbx_to_txt.py, then run python mbx_to_txt.py mailbox.mbx mailbox.txt:

import mailbox
import sys
from email import policy
from email.generator import BytesGenerator

source, target = sys.argv[1], sys.argv[2]
box = mailbox.mbox(source)
with open(target, "wb") as output:
    for message in box:
        BytesGenerator(output, policy=policy.default.clone(linesep="\n")).flatten(message)
        output.write(b"\n\n")

This method writes each message as readable RFC-style headers and body content. It requires Python and works only when the MBX file uses an mbox-compatible layout; a proprietary or damaged mailbox should be imported with a mail client or a dedicated desktop mailbox converter instead.

Quality and compatibility limitations

TXT conversion can change character encoding, line endings, and the representation of HTML email. Select UTF-8 when the converter offers an encoding option; otherwise, accented characters and non-Latin scripts may appear incorrectly.

Attachments are usually represented only by MIME headers or encoded blocks unless the conversion tool extracts them separately. If attachments matter, export messages to EML or preserve the original MBX before creating the TXT copy.

The related .toc file is generally not required for direct extraction, but keeping it with the original mailbox can help legacy Eudora software reconstruct message indexes. Never use the TXT output as a replacement for the original if message metadata, attachments, or later re-import are required.