Mbox Viewer by Cloud Captains

Tracking since Apr 1, 2026.

Changelog

• May 20, 2026
  short_description

  Secure, private, offline Mbox/EML/EMLX/Maildir viewer with forensic analysis, search, tags and bulk export. 100% local, no uploads.

  Mbox Viewer: secure, private, offline Mbox/EML/EMLX/Maildir viewer. Forensic analysis, search, bulk export. 100% local.

• Apr 29, 2026
  description

  Mbox Viewer by Cloud Captains is the simple, secure, and completely private solution you've been looking for. It works 100% offline, right in your browser, ensuring your data never leaves your computer.
  
  This tool was built out of a simple need for a fast, reliable way to view Mbox archives without compromising on privacy. Whether you're opening a Google Takeout export or accessing old email backups, our viewer gives you instant access without any fuss.
  
  All features are available for free, with no ads or hidden costs. This is a tool built for the community.
  
  Why Mbox Viewer?
  
  ‣ Truly private and secure: Your files are processed locally on your machine. We never see, store, or transmit your data. What's yours stays yours.
  ‣ Works completely offline: After the initial page load, the viewer functions perfectly without an internet connection, making it reliable and secure wherever you are.
  ‣ Fast and powerful: Opens large Mbox files and even entire folders of Mbox files with ease. The powerful search and filtering tools help you find exactly what you're looking for in seconds.
  ‣ Simple and intuitive interface: No complicated setup. Just drag and drop your file or folder to get started. View emails in a clean preview, or inspect the raw source.
  
  Key features include:
  ⋅ Drag-and-drop support for single or multiple .mbox files.
  ⋅ Ability to open an entire folder of Mbox files at once.
  ⋅ Powerful text search across all emails.
  ⋅ Advanced filtering by date, sender, subject, and attachments.
  ⋅ Clean email preview with attachment handling.
  ⋅ Dark and light themes for comfortable viewing.
  ⋅ Export individual emails to PDF, EML, or HTML formats.
  
  --- What's New in Version 1.5 ---
  ‣ Processing Engine: We've completely rebuilt the file handler for unmatched stability and speed, especially with huge archives.
  ‣ Dual-Mode Handling: The app now automatically uses a high-speed memory mode for smaller files (< 1 GB) and a robust database mode for huge archives, preventing browser crashes.
  ‣ New Welcome Guide: A new one-time introduction screen helps first-time users understand the app's power and performance expectations.

  Mbox Viewer by Cloud Captains is the simple, secure, and completely private solution for reading email archives. It works 100% offline, right in your browser, so your data never leaves your computer.
  
  This tool was built for people who need a fast, reliable way to view Mbox archives without compromising on privacy. Whether you are opening a Google Takeout export, an old backup, or running an investigation on suspicious mail, the viewer gives you instant access with no setup.
  
  All features are free, with no ads, no trackers, and no hidden costs.
  
  Why Mbox Viewer?
  
  - Truly private: your files are processed locally. We never see, store, or transmit your data.
  - Works completely offline: the viewer functions without an internet connection.
  - Fast and powerful: opens large Mbox archives and entire folders with ease.
  - Simple and intuitive: drag and drop your file or folder to get started.
  
  Key features:
  
  - Drag and drop support for .mbox, .mbx, .eml, .emlx, Maildir and .mbox.gz archives.
  - Open an entire folder of Mbox files at once.
  - Gmail-style search operators: from, to, subject, has:attachment, before, after, larger, is:starred, filename, plus regex mode and saved searches.
  - Advanced filtering by date range, source file, attachments, starred and tags.
  - Clean email preview with inline attachment handling and external image blocking.
  - Forensic analysis tab with SPF, DKIM and DMARC verdicts, suspicion scoring on 9 signals, SHA-256 and MD5 hashes, Received-chain and a visual email route with TLS status and timing.
  - Multi-select with bulk export to EML, PDF, HTML, CSV, MBOX or a password-protected case file with AES-256 encryption.
  - Free text tags, stars, notes and saved searches, stored locally.
  - Tag and notes overview pages with bulk export.
  - Dark, light and system themes with high-contrast mode.
  - Keyboard shortcuts: j and k to navigate, Enter to open, a to select all, slash to search, s to star, t for tags, question mark for the guide.
  - Print friendly layout and export per email to PDF, EML or HTML.
  
  Built by Cloud Captains, a Google Workspace Partner. Learn more at https://cloud-captains.com. Questions, bugs or feedback please go to https://mbox-viewer.online/

• Apr 29, 2026
  short_description

  Secure, private, and 100% free Mbox file viewer that works offline. Read your email archives without ever uploading your data.

  Secure, private, offline Mbox/EML/EMLX/Maildir viewer with forensic analysis, search, tags and bulk export. 100% local, no uploads.

Permissions & access

Permissions

None declared

Host access

None declared

Screenshots

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