Corbett

MBOX Converter

Corbett MBOX Converter opens MBOX files from Thunderbird, Apple Mail and Google Takeout on Windows and saves mail as PST, EML, PDF, HTML, TXT or CSV. Folders, dates and attachments stay intact, and no mail app needs to be installed. Try free demo first.

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4.6 out of 5 from 683 reviews

Works offline on your PC. Corbett never sees your MBOX file or messages.

Free demo, scanned clean on VirusTotal and a 30-day money-back window.

Lifetime licence from $99 Demo converts 10 emails per folder

Quick answer

What Is an MBOX Converter?

An MBOX converter opens an MBOX mailbox file and saves its emails and attachments in another format. Corbett MBOX Converter does that offline on Windows, so mail from Thunderbird, Apple Mail or Google Takeout opens in Outlook, a PDF viewer or any email client.

What it opens

Single MBOX files, entire folders of them and Google Takeout mail

What it saves

PST, EML, PDF, HTML, TXT, CSV, MBOX and more

Who uses it

Switchers, admins, lawyers and anyone with an old MBOX

Conversion scope

MBOX Converter for Any MBOX File

MBOX Converter Frees Mail Stuck in One Big File

An MBOX file stores a full mail folder as one long text file, with every message stacked under a separator line. Few programs open it, and fewer cope once it grows large. MBOX converter splits that file back into separate messages and leaves your MBOX as it was.

Kept in output

Folder tree
Attachments
Inline images
Message dates
Full headers

MBOX sources

Thunderbird
Apple Mail
Google Takeout
Orphan .mbox files from old PCs

Outputs

PST
EML
PDF
HTML
TXT
CSV
MBOX

Not needed

Thunderbird install
Apple Mail install
Internet connection
Mailbox password

One file, many emails

RFC 4155 defines MBOX as many messages in one file, and Thunderbird still calls it the traditional format, as the Mozilla Thunderbird Maildir page says. That is why a big MBOX is slow to open and hard to share. MBOX Converter splits it into a format you can use.

Open MBOX file

Related pages: PST Converter, EML Converter, OLM Converter and MSG Converter. Other mail files sit on email converter tool page.

Core features

MBOX Converter Features by Screen

Five screens of Corbett MBOX converter software, in conversion order.

MBOX converter list of supported mail file types

Source files

Open Your MBOX File

Select Open, then Email Data Files, and choose MBOX Files. MBOX converter fills its panel with your mail, and no Thunderbird or Apple Mail is needed.

A spare PC with no mail app still works. MBOX file converter reads your file and leaves it as it was.

Batch loading

Choose Files or Choose Folders

Select Choose Files for one or a few MBOX files. Select Choose Folders to load an entire directory of them in one step.

Loaded files appear in one tree with their folder names, so MBOX converter handles many MBOX files in a single session. No file size limit applies.

MBOX converter email preview with content, header, hex and raw views

Message preview

Preview MBOX Emails Before Converting

Click any message and a reading pane opens beside four analysis views. Use them to check dates and senders before an audit or legal export.

Content shows the body and address fields. Message header lists routing details such as sender, recipient and date. Hex and raw message views show the stored message byte by byte.

MBOX converter export menu with email file and document formats

Output formats

Select Your Output Format

Email files export to PST, EML or MBOX. Document files export to PDF, HTML, TXT or CSV. The Export menu also lists Gmail, Office 365, IMAP and Thunderbird for sending mail into an account.

Search by keyword first, then save only matched items. Quick search highlights hits in yellow, and Advance search checks every field or only name, subject, To, Cc and content.

Export options

Set MBOX Export Options Before You Save

Switch on open folder after export, skip greyed out folders, create empty folders and include email headers. For PST output, create an individual PST file for every folder, so small files stay healthy.

Select Browse to choose a destination, then Save. Live progress shows every folder as it converts. Need Outlook files? Open MBOX to PST Converter.

Working process

How to Convert an MBOX File in Four Steps

Four steps take an MBOX file to its new format. Try them on one file in free demo first.

Open your MBOX file

Start MBOX converter, select Open, then Email Data Files and choose MBOX Files. Select Choose Files for one file or Choose Folders for many.

Preview and select folders

Your MBOX loads as one folder tree. Click any email to preview it, tick folders and search by keyword to trim your conversion.

Choose your output

Select Export and choose a format: PST, EML or MBOX for email files, PDF, HTML, TXT or CSV for documents.

Save your converted mail

Set options, select Browse for a folder and press Save. Live progress shows every folder, and Open Folder takes you to your output.

Want screenshots for every click? Follow MBOX converter guide.

Working process

MBOX Converter Video Walkthrough

Prefer text? Open Open MBOX file to see what an MBOX holds before conversion.

Advanced options

More MBOX Converter Features for Big Jobs

Small options that save hours when you convert MBOX files in bulk.

Batch MBOX conversion

Many MBOX files converted in one session

No file size limit

Large MBOX files convert too

Folder hierarchy kept

Inbox, Sent and subfolders stay in order

Attachment extraction

Save attachments alone from any MBOX

Email address extraction

Export addresses to CSV

Phone number extraction

Pull numbers from message bodies

File naming options

Name output by From, To, Date or Subject

Smart filters

Date, sender, subject and size

Quick and advance search

Find emails before you convert

Four preview views

Content, header, hex and raw message

Individual PST per folder

One PST file for every folder

Log and CSV report

See what converted and what failed

USB and NAS targets

Save output to external drives and network storage

Include email headers

Keep full header data in output

Takeout files too

Google Takeout mail sits beside MBOX in one list

Choose output

MBOX Converter Output Formats

MBOX converter saves to nine file formats. Match format to where your converted mail will open.

Format	Best for	Opens in
PST	One file per mailbox with folders intact	Microsoft Outlook
MBOX	Moving mail to a free email client	Thunderbird and Apple Mail
EML	One file per email, easy to search	Windows Mail and most email clients
PDF	Legal files, audits and printing	Any PDF viewer
HTML	Reading mail with no email client	Any web browser
TXT	Plain text archives	Any text editor
CSV	Lists of senders, dates and subjects	Excel and Google Sheets
vCard	Contacts moved into a phone or address book	Outlook, Gmail and phones
ICS	Calendar entries shared between apps	Outlook, Google Calendar and Apple Calendar

Free demo

Test MBOX Converter on a Real MBOX

Install free demo, open an MBOX file, select a folder and choose a format. Free demo converts 10 emails per folder, so your output is quick to check.

Download free demo

Try before you buy

Free Demo vs Full MBOX Converter

Free demo opens, previews and searches your full MBOX. Only conversion is capped.

Feature	Free demo	Full version
Open MBOX and load folders	Yes	Yes
Preview, search and analysis views	All available	All available
Emails converted per folder	10	Unlimited
MBOX size and file count	Conversion stops at 10 per folder	No limit
Price	Free	From $99 one time

Use cases

Who Needs an MBOX Converter?

Anyone who must convert an MBOX file that will not open where needed.

People switching to Outlook

MBOX converter saves Thunderbird and Apple Mail folders as PST and keeps folders in place.

Gmail users with a Takeout file

Takeout hands you MBOX files. Convert MBOX files to PST, PDF or EML and open your Gmail history anywhere.

Legal and compliance teams

Convert MBOX emails to PDF with sender, date and attachments named clearly for case files and audits.

IT admins after a switch

MBOX converter saves leftover MBOX files from retired PCs and Macs in formats users open without the old client.

Investigators

Preview message header, hex and raw views for an MBOX of unknown origin before you export.

Marketers and list builders

Export addresses and phone numbers from an old MBOX to CSV for outreach.

Why Corbett

Why Choose Corbett MBOX Converter?

No subscription

Lifetime price from $99

Works offline

No sign-in and no upload

Original stays safe

MBOX opens read only

No mail app needed

Convert MBOX with no Thunderbird

No size limit

Any MBOX size and file count

Folders kept

Hierarchy stays in order

Smart filters

Date, sender, subject and size

30-day refund

Money-back window after purchase

Before conversion

MBOX Converter Scope and Limits

MBOX converter turns a mailbox file into another format. Here is what that covers and where it stops.

Capability	Supported	What it means
File to file conversion	Yes	MBOX to PST, EML, PDF, HTML, TXT and CSV with folders kept
Mail app installed	Not needed	Files open on a PC with no Thunderbird or Apple Mail
Source MBOX	Read only	Output goes to a new folder and your original stays as it was
Internet and passwords	Not needed	Conversion works offline on local files
Settings and rules	Not converted	Client settings, saved searches and filter rules stay behind
Live mailboxes	Other mode	Use Email Backup Software or Email Migration Tool for accounts
Mac and Linux	No	MBOX converter installs on Windows only

Free viewer or tool

MBOX Converter vs Free MBOX Viewer

Corbett also offers a Free MBOX Viewer that reads MBOX files at no cost. When mail must live somewhere else, MBOX Converter takes over. Here is where the free one stops.

Task	Free MBOX Viewer	MBOX Converter
Cost	Free	From $99 one time
Read MBOX mail	Reads every message	Reads too, plus export
PST for Outlook	Not offered	Full PST output
Date and sender filters	Search only	Filters applied to export
Batch of files	Opens files	Converts folders in one session
PDF for records	Print only	PDF output
Pull addresses	No	Addresses, phones and attachments

To read old mail without moving it, the free viewer is enough.

Global recognition

MBOX Converter Software Users Trust

Users rate Corbett MBOX converter 4.6 out of 5 from 683 reviews, and these software directories list it.

CNET
Download.io
UpdateStar
TopSoftware Advisor
SaaSHub
Uptodown

Specifications

MBOX Converter Specifications

Download details

Download size: 87.4 MB
Demo limit: 10 items per folder
Delivery: After payment, mail arrives with a download link and a licence key.
Licence: Personal: 5 machines. Business: 25 machines. Enterprise: 100 machines. Lifetime validity.

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System

Hard disk: 150 MB of free space
RAM: 4 GB of memory minimum
Processor: 1 GHz Intel Pentium minimum and 2.4 GHz advised
Interface: English
Input: MBOX files

Supported editions

Windows 11 (64 bit), 10, 8 and 7 in 32-bit or 64-bit, plus Windows Server 2016, 2012 R2 and 2008.

Start MBOX converter with administrator rights.

Corbett has built Windows email utilities since 2020. Setup trouble and first-use questions go to our support desk.

User testimonials

MBOX Converter Reviews

MBOX converter shares 683 reviews on software index sites and customer feedback.

4.6 out of 5

Collected across 683 reviews from software indexes and customer feedback. Three reviews below are unedited.

Thunderbird to Outlook, intact

I like how it is easy to use as I move all my emails from Thunderbird to Outlook. It worked so well that my folder structure and attachments were intact after converting them.

Jenna

Old MBOX files to PDF

I had a batch of old MBOX files that needed to be converted into PDF. With the help of this converter, my process of converting has become so simple. I highly recommend this tool to everyone.

Michael

Date filter did the job

I loved the option of filtering the emails by date. This feature helps me to convert specific emails from MBOX files. Plus with so many export options there's no need for any other tool to convert the files.

Daniel

Before conversion

Prepare Your MBOX File for Conversion

Most failed conversions trace back to the file. Three checks keep your MBOX conversion clean.

Unzip Google Takeout first

Takeout delivers an archive. Extract it, then load the .mbox file inside. Files are named after your Gmail labels.

Apple Mail needs the package

Apple Mail guide to exporting mailboxes says Mail exports every mailbox as an .mbox package. Copy that package to your Windows PC and load it into MBOX converter.

Thunderbird: skip the .msf files

Thunderbird keeps every folder as an MBOX file with no extension next to a .msf index. Load the file without an extension into MBOX converter.

Need to export first? Read Export Gmail emails to MBOX or Export MBOX from Thunderbird.

Best practice

How to Keep Your MBOX Conversion Safe

An MBOX conversion only helps if your mail arrives complete. Four habits keep your data safe through it.

Back up first

Copy your original MBOX before you start. Keep 3 copies on 2 types of media with 1 copy off site.

Start with a small MBOX

Convert one small file with MBOX converter and open a few messages in your new format. Catch a wrong setting before a large job.

Close your mail app

Quit Thunderbird or Apple Mail before you copy its MBOX files, so MBOX converter gets a complete file.

Keep originals until checked

Store your source MBOX files until folder counts match. Delete them only after you open converted mail.

Common questions

MBOX Converter FAQs

MBOX converter steps, sources, formats, limits and licence answers.

What is an MBOX converter?

An MBOX converter opens an MBOX mailbox file and saves its emails and attachments in another format. Corbett MBOX Converter does that offline on Windows, so MBOX file converter needs no mail app.

How do I convert an MBOX file with attachments?

Open MBOX converter, select Open, then Email Data Files and MBOX Files. Choose Files or Choose Folders, preview your mail, select Export, choose a format and press Save. Attachments stay with every message.

Which programs create MBOX files?

Thunderbird and Apple Mail write MBOX, and Google Takeout hands out Gmail as MBOX. Mozilla Thunderbird Maildir page calls it the traditional Thunderbird format, and Apple Mail guide to exporting mailboxes says Mail exports mailboxes as .mbox packages.

Can I convert a Google Takeout file?

Yes. Extract your Takeout archive and load the .mbox file inside into MBOX converter. Google Takeout mail also sits in the Email Data Files list.

Does it convert Apple Mail exports?

Yes. Apple Mail guide to exporting mailboxes says Mail exports every mailbox as an .mbox package. Copy the package to your Windows PC and load it.

Which formats can I convert an MBOX file to?

PST, EML and MBOX for email files, plus PDF, HTML, TXT and CSV for documents. The Export menu also lists Gmail, Office 365, IMAP and Thunderbird for sending mail into an account.

How do I convert MBOX to PST?

To convert MBOX files to PST, select PST in the Export menu, set options such as an individual PST for every folder and press Save. MBOX to PST Converter shows every click, and Import MBOX to Outlook account covers the Outlook side.

How do I convert MBOX to PDF?

Select PDF in the Export menu, search for the emails you need, choose a naming option and press Save. Every message becomes a PDF. MBOX to PDF Converter covers that job.

Can I convert MBOX to EML?

Yes. Select EML for one file per email, with folders kept in order. Open MBOX to EML Converter for that job.

Can I convert many MBOX files at once?

Yes. Select Choose Folders and load an entire directory, then MBOX converter converts every file in one session.

Is there an MBOX file size limit?

No. MBOX converter sets no size cap, and large MBOX files convert too. Keep free disk space for your output.

Can I convert only some emails from an MBOX file?

Yes. Search by keyword with quick search, or use Advance search across every field or only name, subject, To, Cc and content, then save matched items.

Can I preview MBOX emails before converting?

Yes. A reading pane opens beside content, message header, hex and raw message views for every email.

Does it keep my folder structure?

Yes. Folder hierarchy stays in order, so Inbox, Sent and subfolders arrive as they were.

Do I need Thunderbird or Apple Mail installed?

No. MBOX converter reads your file by itself, so orphan files from a dead PC or an old Mac work too. No internet connection or mailbox password is needed.

Will converting change my original MBOX?

No. Your MBOX opens read only, and output goes to a new folder. Keep a spare copy anyway.

Can I extract email addresses and attachments from MBOX?

Yes. Export addresses to CSV, pull phone numbers from message bodies and save attachments alone. MBOX to CSV converter shows the steps.

Can I convert MBOX to HTML or text?

Yes. Select HTML or TXT in the Export menu. Convert MBOX to HTML and Convert MBOX to text file format show every click.

Can I move MBOX straight into Gmail?

The Export menu lists Gmail, Office 365 and IMAP. Read Import MBOX to Gmail and Import MBOX to Office 365 mail for the steps.

Does my MBOX pass through Corbett?

No. Conversion happens on your PC with no upload. Corbett never sees your MBOX or messages.

Can I convert MBOX on a Mac?

Not on the Mac itself. Copy your MBOX files to a Windows PC and convert them there.

How many emails can free demo convert?

Free demo opens your MBOX, shows every folder and gives you every search and preview. Conversion stops at 10 messages per folder, enough to test your output before you buy.

Which Windows versions work?

Windows 11 (64 bit), 10, 8 and 7, plus Windows Server 2016, 2012 R2 and 2008. There is no macOS or Linux build.

How many PCs does one licence cover?

Personal licence covers 5 machines for $99, Business covers 25 for $299 and Enterprise covers 100 for $499. All three are one time payments with lifetime validity, 24/7 support and a 30 day refund.

MBOX guides