---
title: "A complete, native MBOX toolkit — Mbox Viewer"
description: "Everything you need to open, search, read and export huge email archives on Mac and Windows — without a web app in a window."
url: https://mboxviewerpro.com/features/
language: en
source: Mbox Viewer
---

# A complete, native MBOX toolkit

Everything you need to open, search, read and export huge email archives on Mac and Windows — without a web app in a window.

See how it works

## Mbox Viewer in one minute

Recorded on macOS with a sample mailbox. Mbox Viewer is also available for Windows, where the interface differs slightly.

## Built for scale

### Any file size

A streaming parser with a 1 MB buffer opens files from a few KB to 50+ GB without ever loading them into RAM.

### Instant re-opens

A binary index with SHA-256 validation makes every re-open take under a second, regardless of size.

### Low memory footprint

Even a 50 GB archive stays under 600 MB of RAM thanks to on-demand streaming and an LRU message cache.

### Repair damaged mailboxes

Deep-scan recovery re-detects lost message boundaries and exports a repaired copy — the original file is never modified. (Pro)

## Find anything

### Powerful search syntax

Use from:, to:, subject:, body:, date:, has:attachment, size:>, OR, negation and exact phrases — or the visual filter sheet.

### Gmail labels

Reads Gmail labels straight from Takeout. Browse by label in the sidebar with live message counts.

### Conversation threading

The JWZ algorithm groups messages into conversations with visual reply chains up to four levels deep.

### Properties, MIME & Hex views

Three new ways to inspect a message: a Properties panel, the MIME part tree and a raw hex dump — ideal for technical or forensic work.

## Get your data out

### Export anywhere

Export to EML, CSV (Excel-ready, UTF-8 with BOM) or plain text, and extract attachments in bulk.

### Export a selection as a new MBOX

Narrow a huge archive down by search, by Gmail label or by hand, and write the result to a brand-new mailbox that contains only those messages — the delivery step of a legal hold or a public-records request. The original file is never modified.

### Merge & dedupe MBOX

Combine multiple MBOX files into one, with optional Message-ID deduplication. Export a single label as its own MBOX.

### Attachments

View attachments inline, preview with Quick Look (Spacebar), save individually or in bulk, or drag straight to Finder (Explorer on Windows).

### Export to PDF

Export any message to a self-contained, multi-page PDF with the same layout as printing. One message is free; batch export is Pro.

### Export to HTML

Save any message as a self-contained HTML file with images embedded and attachments as downloadable links — it opens anywhere. One message is free; batch is Pro.

## Native & private

### Truly native on Mac & Windows

Native on Mac (SwiftUI + AppKit) and Windows (WinUI). Dark mode, drag & drop, system share, print and full keyboard navigation. No Electron, no Java.

### Privacy by design

Everything runs locally. No cloud, no telemetry, no account. Remote images blocked and HTML sanitized by default.

### Drag & Drop everywhere

Drop MBOX or EML files onto the app to open them, and drag messages out as .eml or attachments to Finder.

## Search syntax at a glance

Combine prefixes, operators and exact phrases to pinpoint any message.

<table class="w-full text-left text-sm"><tbody><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">from:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">from:john@example.com</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Messages from this sender</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">to:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">to:team@</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Sent to this address</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">subject:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">subject:"quarterly report"</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Subject contains phrase</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">body:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">body:invoice</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Full-text body search</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">has:attachment</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">has:attachment</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Messages with attachments</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">label:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">label:Important</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Gmail label</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">date:</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">date:2024-03</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">From a given month</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">size:&gt;</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">size:&gt;5mb</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Larger than a size</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">-</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">-spam</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Exclude a term</td></tr><tr class="border-b border-ink-100 last:border-0 dark:border-ink-800"><td class="whitespace-nowrap px-4 py-3 font-mono text-xs font-semibold text-brand-600 dark:text-brand-300">OR</td><td class="whitespace-nowrap px-4 py-3 font-mono text-xs text-ink-500 dark:text-ink-400">from:alice OR from:bob</td><td class="px-4 py-3 text-ink-600 dark:text-ink-300">Either condition</td></tr></tbody></table>

## Available in 18 languages

Mbox Viewer's interface and user guide are localized into 18 languages, so you can work through your email in the one you know best.

-   English
-   Español
-   Deutsch
-   Français
-   Italiano
-   日本語
-   한국어
-   Nederlands
-   Polski
-   Português (BR)
-   Português (PT)
-   Русский
-   Svenska
-   Dansk
-   Norsk
-   Türkçe
-   简体中文
-   繁體中文

## Free vs Pro, line by line

Same app, same interface, same 18 languages. Pro is not a different program: it is these four things.

| What you can do | Free | Pro |
| --- | --- | --- |
| Maximum mailbox size | 1 GB | Unlimited |
| Search, Gmail labels and conversation threads |  |  |
| Export to EML, CSV, plain text and MBOX |  |  |
| Extract attachments in bulk |  |  |
| Properties, MIME tree and hex views |  |  |
| Export to PDF and HTML | One message | In batches |
| Merge mailboxes with deduplication | Up to 1 GB combined | Unlimited |
| Repair damaged mailboxes |   |  |

Pro is a one-time in-app purchase on the Mac App Store or the Microsoft Store — no subscription, no account, no licence key. The price is the one your store shows for your country.

[Try it on your own archive](https://apps.apple.com/app/mbox-viewer-pro/id6759237715) [Microsoft Store](https://apps.microsoft.com/store/detail/9NW3GVFG7DDB)