Open MSG and EML on Mac

Open MSG, EML,
MHTML and MBOX
files on your Mac.

MailPeek is built for people who receive .msg, .eml, .mht/.mhtml or .mbox files and need to open them fast on macOS. Inspect content, headers, source and attachments locally, with remote content blocked by default.

One-time purchase · 3,99 € · No subscription · No hidden fees

MailPeek app showing email inspection interface on macOS
Supported formats .msg .eml .mhtml .mht .mbox winmail.dat

Features

Built around the workflows that matter
when email files land on your Mac.

📂

Open MSG on Mac

Open Outlook .msg files directly on macOS. Inspect instantly without converting, forwarding or importing into another mail client first.

🔍

Headers and Source

Verify sender data, routing and raw message source. Switch into Headers or Source view when you need the technical truth instead of just the rendered body.

📎

Attachment Safety

Review attachments before you open them. Make risky files visible, inspect names and types, and handle winmail.dat containers cleanly.

↕️

Import and Export

Open .mbox archives, then export inspected mails as PDF, HTML, TXT, EML or VCF.

📦

Multiple Files

Work with many messages in one session. Browse the sidebar, search by filename, sender or subject, and triage without opening one file at a time.

🔒

Privacy First

Local inspection — no cloud round-trip. Remote HTML is blocked by default. All processing happens on your Mac, offline-capable.

Feature Matrix

Everything MailPeek helps you inspect, export and verify.

Formats

.msg, .eml, .mht/.mhtml and .mbox support.

Search

Search by filename, subject, sender and recipient.

Views

Email, Headers and Source in one workflow.

Finder

Quick Look preview for MSG files.

Export

Export to EML, TXT, HTML, PDF and VCF.

Batch Export

Export multiple open mails in a single run.

Attachments

Open, Download and Download All actions.

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Safe Mode

Restrict unsafe files and preserve quarantine behavior.

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TNEF

winmail.dat decoding with extracted embedded files.

Headers

From, To, Reply-To, Cc, Bcc and date visibility.

Source

Raw message source for debugging and validation.

Rendering

HTML, RTF and plain text body modes.

Remote HTML

Load external content only when explicitly allowed.

Privacy

All processing happens locally on your Mac.

MBOX Import

Handles large files and Apple Mail export structures.

Drag and Drop

Drop one file or many files directly into the app.

Workflow

Multi-file sessions, sidebar search and close-all actions.

Contacts

Export addresses from headers as VCF.

Appearance

Light-first UI with Dark Mode support in the app.

Offline

Core inspection features work without an internet connection.

Mac App Store

  • One-time purchase
  • No subscription
  • Ready when a raw mail file lands on your desktop

MailPeek is a dedicated utility, not a mailbox replacement. It exists to open difficult message files fast and give you the technical detail you actually need.

One-time

3,99 €

No hidden fees. Ever.

Download on the App Store

FAQ

Short answers before you buy

Which formats does MailPeek support?

MailPeek supports .msg, .eml, .mht/.mhtml and .mbox.

Does it upload email files anywhere?

No. Processing is local on your Mac, and remote content is blocked by default.

Can I inspect headers and raw source?

Yes. MailPeek provides separate Email, Headers and Source views.

Can I open several files at once?

Yes. You can drag multiple files into one session and search across them in the sidebar.

Does MailPeek support Outlook MSG files on macOS?

Yes. MailPeek is built specifically to open and inspect .msg files on macOS.

Can I open MBOX archives and Apple Mail exports?

Yes. MailPeek supports standard .mbox files and Apple Mail export structures.

Does MailPeek support HTML, RTF and plain text bodies?

Yes. When available, MailPeek lets you inspect different body representations of the same message.

Can I work offline?

Yes. Core inspection features work offline because message files are processed locally on your Mac.

How does remote content work?

Remote HTML content is blocked by default. You can explicitly allow it per message when you need to inspect it.

Does MailPeek warn about unsafe attachments?

Yes. Risky attachment types and double extensions are visually flagged before you open them.

What is Safe Mode?

Safe Mode adds attachment safety checks and can preserve quarantine behavior for suspicious files.

Can MailPeek decode winmail.dat files?

Yes. MailPeek decodes winmail.dat containers and exposes extracted embedded files.

Can I export messages after inspection?

Yes. MailPeek supports export to EML, TXT, HTML, PDF and VCF.

Does it support batch export?

Yes. You can export multiple open messages in one run and choose several output formats.

Can I preview MSG files in Finder?

Yes. MailPeek includes Finder Quick Look support for .msg files.

Is MailPeek a subscription?

No. MailPeek is sold as a one-time purchase on the Mac App Store.

Does the app support Dark Mode?

Yes. MailPeek supports Dark Mode and follows your macOS appearance settings.