Summary
Logos books will soon be smaller to download, and quicker to open for our users. Books published on or after March 10, 2026 will require Logos v38 or later. We sometimes update existing books (e.g., to fix typos or formatting). Any book updates released on or after March 10, 2026 will also require v38. If you’re on an earlier version of Logos, you’ll continue to have access to the previous book file version.
Details
Logos is constantly publishing new books in our format, as well as updating older books for typo corrections and other improvements. We are making an internal, technical change to how we compile and ship Logos book files: We are implementing a new compression standard in our book compiler, making Logos books smaller and more efficient. This is a behind-the-scenes change that will happen seamlessly in the background. You won’t see any difference in the way these books look or work in Logos, except they might be just a little faster.
On March 10, 2026, we will start shipping book files in the new standard, both for newly-published books, and for updates to existing books.
Logos version 38 or later will be required to use this new file standard. To make sure as many users as possible will benefit from this change, we added support for it to the app over a year ago, when we shipped v38 in December 2024. We also shipped an update that would allow users to install on an older version of macOS, to make sure no one was left behind. The vast majority of Logos users are now running v38 or higher, so we are ready to start delivering books in the new standard.
What do I need to do?
You probably don’t need to do anything. Updating to Logos’s current software version is free for all users, and automatic updates are turned on by default. Most users are already running the stable version of Logos (version 48, at time of writing).
If you have turned off automatic updates, check your version of Logos (under the ⋮ app menu > About Logos) to make sure you have at least version 38 installed.
To manually update to the latest version of Logos:
- Open Logos, and enter the command update now in the Go box.
OR - Download the installer for the current version of Logos at www.logos.com/install.
What if I can’t update to v38?
You won’t be able to update Logos if you are running macOS 11 or older, or Windows 10 v1703 (2017) or older.
If you are stuck on an older version of Logos, here’s what will and won’t work:
- You can still use Logos. Logos will continue to function mostly as normal; though since you are running an older version, it’s not eligible for support.
- You will still have all of your books. Older versions of book files will still be available to download and use, and Logos will automatically download the book file that works best with your version of Logos.
- You won’t be able to get book updates, or newly-published books. If you buy a book that is published for the first time in Logos after March 10, 2026, it won’t work on your version of Logos. (If you buy a book that was published before then, your Logos will download an older version of the file.)
As always, you can also access all your books at app.logos.com, which is always running the latest version.
