How this started
A few years ago I was helping a relative switch away from a costly Microsoft Office subscription. Moving to free alternatives was mostly painless — Thunderbird handled email well, LibreOffice took care of documents — but when it came to migrating the PST files out of Outlook, things ground to a halt.
I went looking for tools to help. The commercial options I found were either expensive, riddled with dark patterns, or required uploading a private email archive to a server somewhere on the internet. None of those felt like good choices. So I spent the better part of a few days cobbling together a solution using command-line tools, Google searches, and no small amount of help from AI — eventually getting there, but with considerably more grey hairs than I started with.
I went looking for tools to help. The commercial options I found were either expensive, riddled with dark patterns, or required uploading a private email archive to a server somewhere on the internet. None of those felt like good choices. So I spent the better part of a few days cobbling together a solution using command-line tools, Google searches, and no small amount of help from AI — eventually getting there, but with considerably more grey hairs than I started with.
The moment it became a product
Some time later, a second relative asked me for help with exactly the same problem. Regrettably, I am the family IT expert.
At that point I decided enough was enough. Instead of going through the same painful process again, I sat down and built the tool I wished had existed in the first place: something solid, straightforward, completely offline, and priced like a useful utility rather than enterprise software.
So I give you PST to Mail, PST to Thunderbird, and PST Viewer. Not the most exciting software in the universe — but it might just save you from smashing the monitor in frustration.
At that point I decided enough was enough. Instead of going through the same painful process again, I sat down and built the tool I wished had existed in the first place: something solid, straightforward, completely offline, and priced like a useful utility rather than enterprise software.
So I give you PST to Mail, PST to Thunderbird, and PST Viewer. Not the most exciting software in the universe — but it might just save you from smashing the monitor in frustration.
What the tools do
PST to Apple Mail
Converts Outlook PST files into Apple Mail on macOS. Offline, no Outlook required, folders and attachments preserved.
PST to Thunderbird
Converts Outlook PST files into Thunderbird on Mac, Windows or Linux. Same offline approach, same results.
PST Viewer
Opens and browses PST files on any platform without converting them. Completely free — no licence required.
The design principles
Having lived the problem, I was clear about what these tools had to be:
- Offline. Your email archive is private. It should stay on your own machine — not pass through someone else's server.
- Simple. The people who need to migrate PST files are not usually the people who enjoy command-line tools. The process should take minutes, not days.
- Affordable. PST to Thunderbird and PST Viewer are completely free. PST to Apple Mail is a one-time $9.99 licence — no subscription, no annual fee, no upsell.
- Honest. No dark patterns, no artificial limitations in a "free" tier designed to frustrate you into upgrading.
About Khulan Ltd
PST to Mail is a product of Khulan Ltd, a software company founded by Derek McDoon in 2015. Khulan has been building quality business software for over a decade, with a focus on tools that solve real problems cleanly and without unnecessary complexity.
Get in touch
If you have a question, run into a problem, or want to share feedback, we'd love to hear from you. Email us at .
Download the tools
PST Viewer & Thunderbird Converter are free · PST to Apple Mail — $9.99 one-time