Most online file converters work by uploading your file to a server, converting it there and sending the result back. That's fine for a holiday photo. It's not fine for years of private email, client correspondence or HR records. InboxVue takes a different approach: the whole job happens inside the browser tab on your own computer.
What happens when you open a file
- You choose a file. When you drop an EML, MSG, MBOX or winmail.dat file on InboxVue, the browser gives the page permission to read that one file. That's a standard browser feature; it doesn't give access to anything else on your disk.
- Your browser parses it. InboxVue's code, downloaded once like any web page, runs in background workers in your browser. It reads the file in chunks, decodes the email format and builds a list of messages. Large MBOX mailboxes are indexed as they're read, so you can start reading before the scan finishes.
- You read and search. Messages are displayed in a locked-down viewer, and the search index is held in your browser's memory, or in its private on-device storage for very large mailboxes.
- You export. When you save a PDF, ZIP or CSV, it's built in your browser and written straight to your disk. The EML to PDF export, for example, never touches a server.
At no point is message content, an attachment, a file name or a subject sent over the network. You can check this yourself: open your browser's developer tools, choose the Network tab and watch while you open a file. You'll see no upload.
What does go over the network
InboxVue isn't completely offline, and we want to be precise about what it sends:
- The website itself. Your browser downloads InboxVue's pages and code, like any website.
- Anonymous usage statistics. If you allow analytics, Google Analytics receives page views and events such as "an MBOX file between 100 MB and 1 GB was opened". These events never include file names, subjects, email addresses or message content.
- Sign-in and purchases. If you buy InboxVue Pro, your email address goes to our server and to Polar, our payment provider, and we send you sign-in links by email. Your email files are never part of this.
- Remote images, only if you allow them. Many marketing emails load images from the sender's server. InboxVue blocks them by default, because loading them can tell the sender that you opened the message. You can allow them per message.
Our privacy policy lists every service involved and what each one receives.
How the viewer protects you
Emails can contain hostile content. InboxVue's viewer is built to be safe even with a malicious message:
- Scripts never run. Each message is shown in a sandboxed frame that is not allowed to execute scripts or access the rest of the page.
- Remote content is blocked until you choose to load it.
- Links are checked. Clicking a link in an email shows its real destination on a confirmation page before you leave InboxVue, so a disguised link can't take you somewhere unexpected.
- Attachments aren't opened automatically. You choose whether to preview or download each one.
Remembering files on your device
By default, InboxVue forgets everything when you close the tab. If you turn on "Remember opened files on this device", it keeps your recent files and search index in your browser's private storage on that computer only, so large mailboxes reopen instantly. "Clear local data" deletes all of it. Nothing is synced to a cloud.
Why this design
Processing locally is more private, but it's also practical: there's no upload wait for a 5 GB mailbox, no file size cap imposed by a server, and conversions keep working on a slow connection once the page has loaded. The trade-off is that performance depends on your computer, so very large exports are faster on a desktop than on a phone.
Questions
If you want to know more about how a particular feature handles your data, or you're assessing InboxVue for your organization, contact us. Plans and features are on the pricing page.