100% Private & Secure

Free MBOX Converter
Convert to Any Format

Convert MBOX, MBX, and MBS files to EML, EMLX, MSG, PST, PDF, CSV, HTML, TXT, or JSON. Supports Thunderbird, Gmail Takeout, Yahoo, Apple Mail, and more.

9 output formatsBatch file supportThunderbird & Gmail compatibleInstant conversion

Drop MBOX files here

or click to browse · select multiple files

What Is MBOX Conversion?

MBOX is a standard format for storing many email messages in one file. Messages are separated by a line starting with "From " (the word From followed by a space). This format is used by Mozilla Thunderbird, Apple Mail, and by Google when you export mail via Takeout. Converting MBOX means turning that single file into another format — such as one EML file per message, a CSV spreadsheet, a printable HTML (or PDF via Print), or structured JSON.

Our free MBOX Converter processes everything on your device. You drop an .mbox file, choose an output format (EML, PDF, CSV, HTML, TXT, or JSON), and click Convert & Download. The tool splits the file on the "From " separator, parses headers and body (including base64 and quoted-printable decoding), and generates the chosen format. All processing happens on your device; nothing is uploaded.

Common conversion scenarios include moving from Thunderbird to Outlook (MBOX to EML), archiving Gmail Takeout exports as PDF or HTML, and exporting metadata to CSV or JSON for analysis or migration. Because the tool works online, you can use it on Windows, Mac, or Linux without installing email software.

Features of the MBOX Converter

Convert MBOX to multiple formats with a single tool

Multiple output formats

Export MBOX to EML (individual emails), PDF (print-ready), CSV, HTML, TXT, or JSON in one click.

EML download all

Convert each message to a separate .eml file and download all sequentially with one action.

Preview before convert

See email count and a preview table of the first five messages before choosing your output format.

No upload

MBOX is parsed and converted entirely on your device. Nothing is sent to any server.

Private & secure

Your mailbox file never leaves your device. Ideal for personal archives and work email conversion.

Thunderbird & Gmail

Works with MBOX from Mozilla Thunderbird, Apple Mail, and Google Takeout exports.

How it works

How to Convert MBOX Online

Four steps — no install, no sign-up

01
01

Open the MBOX Converter

Go to the MBOX Converter page and you’ll see the upload area.

02
02

Drop your .mbox file

Drag and drop an .mbox file (e.g. from Thunderbird or Gmail export), or click to browse.

03
03

Choose output format

Select EML, PDF, CSV, HTML, TXT, or JSON from the format grid and review the email preview.

04
04

Convert & download

Click Convert & Download. EML downloads each message; other formats download a single file.

Compare Plans

Free vs Paid — MBOX Converter

Get started free, upgrade when you need more power.

Feature
Free
Paid
Daily usage
5 uses/day
Unlimited
File size limit
10 MB
Up to 500 MB
All core features
No software installation
Works on any device
Files stay on your device
Batch processing
Priority support
Upgrade — starting at $6.99/mo
Upgrade to Full Version

Unlock the Full Power of MBOX Converter

Remove daily limits, process larger files up to 500 MB, enable batch processing, and get priority support.

Buy Full Version — $6.99/moor $300 enterprise

File Viewers includes:

  • 21 file viewers included
  • Unlimited daily uses
  • 100 MB file size limit
  • All file formats supported
  • Email analysis tools

Also available in the All Tools Bundle

Q&A

User Q&A

Common questions about MBOX conversion

Why convert MBOX to EML?

EML is a single-message format supported by Outlook, Windows Mail, and many clients. Converting MBOX to EML lets you open each email in Outlook or archive messages individually.

Can I convert Gmail Takeout MBOX?

Yes. Google Takeout exports mail as MBOX. Use this tool to convert those files to EML, CSV, or HTML for use in other apps or for backup.

Is the PDF real PDF or HTML?

The tool generates a printable HTML page with all emails. Use Print → Save as PDF to get a PDF file. No server-side PDF engine is used.

Does CSV include the full body?

CSV includes From, To, Subject, Date, and a short body preview. For full body export, use HTML or TXT.

Use cases

Use Cases for MBOX Conversion

When and why to convert MBOX files

Thunderbird to Outlook

Convert Thunderbird MBOX to EML so you can import messages into Outlook or Windows Mail.

Gmail Takeout to EML

After exporting Gmail as MBOX via Takeout, convert to EML for use in other email clients.

Archive as PDF

Convert an MBOX to a single printable HTML page, then save as PDF for long-term archive.

Data analysis

Export MBOX to CSV to analyze senders, subjects, and dates in a spreadsheet.

JSON for developers

Get structured JSON (headers and body) for scripting, migration, or integration.

Backup in multiple formats

Keep EML for compatibility and HTML or TXT for human-readable backup.

FAQ

Frequently Asked Questions

More answers about the MBOX Converter

Q1. What is an MBOX file?
MBOX is a format that stores many email messages in one file, separated by lines starting with 'From ' (with a space). Thunderbird, Apple Mail, and Gmail Takeout can export mailboxes as MBOX.
Q2. Do you upload my MBOX file?
No. The MBOX Converter processes everything privately on your device. Your file is never uploaded — nothing is sent to our servers.
Q3. What is the difference between EML and MBOX?
MBOX holds multiple emails in one file. EML holds a single email per file. Converting MBOX to EML produces one .eml file per message (downloaded in sequence when you click Download All).
Q4. Can I convert MBOX to PDF?
The tool generates a printable HTML page containing all emails. Use the Print dialog and choose 'Save as PDF' to create a PDF. No server-side PDF generation is used.
Q5. Why do I get multiple EML files?
Each message in the MBOX becomes one EML file. 'Download All' triggers a separate download for each so you can import them into Outlook or other clients that use one .eml per message.
Q6. Does it work with Apple Mail MBOX?
Yes. Apple Mail can export mailboxes as MBOX. Use this converter to turn them into EML, CSV, HTML, or other formats.
Q7. Is the MBOX Converter free?
Yes. The tool is free to use with no sign-up and no file size limit.
Q8. What if my MBOX is very large?
Large files are loaded into memory. Very big MBOX files (e.g. hundreds of MB) may slow performance. Prefer smaller exports or one folder at a time for best results.
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