How to open a .mbox file
A .mbox file is a single file that stores a whole mailbox: many email messages concatenated together. You don't need a mail client to read one — you can open it right here in your browser.
Open your file in 3 steps
- 1
Drag or choose the file
On the home page, drag your .mbox file onto the drop area, or click it to browse for the file on your computer.
- 2
Browse the messages
Every message is listed with its sender, subject and date. If the archive comes from Gmail, you can filter by label.
- 3
Read a message
Click any message to read it. The email is shown safely, with remote images blocked by default and attachments available to download.
How to get a .mbox file
Most email apps can export to .mbox. The most common sources are:
Google Takeout (Gmail)
Go to takeout.google.com, select Mail, and download. Gmail exports your messages as a single .mbox file.
Apple Mail
Select a mailbox, then Mailbox ▸ Export Mailbox… Apple Mail writes an .mbox package to the folder you choose.
Mozilla Thunderbird
Install the ImportExportTools NG add-on, right-click a folder, and choose Export folder to export a .mbox file.
What you can do here
- Read every message with its full HTML formatting, safely sanitized.
- Download attachments straight from a message.
- Filter Gmail archives by their original labels.
- Keep everything private — your file never leaves your device.
Opening very large archives
The online viewer is tuned for files up to 25 MB. A full Gmail Takeout can be several gigabytes — for those, use Mbox Viewer, the native desktop app for Mac (Windows coming soon), which streams archives of any size and adds search and export.