Mailbox messages
Select a message to inspect its parsed headers and body.
Browser-only .mbox inspection
Free MBOX Viewer Online
A free MBOX viewer opens mailbox exports and turns message separators, headers, senders, dates, attachments, and body previews into a readable diagnostic report. Files are parsed locally in your browser.
2
Messages
2
Senders
1
Attachments
Mar 18, 2026 - Mar 19, 2026
Date range
Mailbox source
sample-mailbox.mbox
Message preview
- Subject
- Weekly inbound email digest
- From
- Launch Bot <launch@example.com>
- To
- Support <support@mailparse.dev>
- Date
- Wed, 18 Mar 2026 14:02:55 +0000
- Message-ID
- <digest-123@example.com>
- Envelope
- From launch@example.com Wed Mar 18 14:02:55 2026
Message warnings
- Missing cc header.
- Missing return-path header.
Content type
text/plain
MIME parts
0
Message size
385 B
Body preview
Three new inbound parsing events are ready for review. The attached mailbox export includes customer replies, webhook payload examples, and delivery metadata.
Attachments
No attachment MIME parts were found in this message.
Headers
| Name | Value |
|---|---|
| From | Launch Bot <launch@example.com> |
| To | Support <support@mailparse.dev> |
| Subject | Weekly inbound email digest |
| Date | Wed, 18 Mar 2026 14:02:55 +0000 |
| Message-ID | <digest-123@example.com> |
| Content-Type | text/plain; charset=UTF-8 |
How to use the MBOX viewer
1
Upload or paste an MBOX export
Choose a .mbox file from your computer or paste mailbox source into the editor.
2
Review mailbox-level metrics
Check message count, unique senders, date range, attachments, and parser warnings.
3
Inspect individual messages
Select any message to review its subject, headers, body preview, MIME parts, and attachment metadata.
MBOX viewer FAQ
What is an MBOX viewer?
An MBOX viewer opens a mailbox export and separates it into individual email messages so you can inspect subjects, senders, dates, headers, bodies, and attachments.
Do MBOX files leave my browser?
No. This tool reads the mailbox file with browser JavaScript and analyzes the contents locally. The email data is not uploaded to MailParse.
Which apps export MBOX files?
Gmail, Google Takeout, Thunderbird, Apple Mail, and many email migration tools can export mailbox folders as MBOX files.
Can this viewer inspect attachments?
Yes. It detects MIME parts marked as attachments and shows filenames, content types, dispositions, and encoded sizes when that metadata is present.
Can I use this for email parser debugging?
Yes. It is useful for checking mailbox separators, message headers, MIME structure, attachment metadata, and representative message bodies before importing email into a parser.