Garmin has started rolling out another software update for its latest premium smartwatch lineup, with firmware version 23.12 now available for the Fenix 8 series and several related models. The update arrives only a few days after the previous beta release, but unlike a major feature drop, this version is mainly focused on improving stability and fixing smaller issues.
The new Garmin beta update applies to the Fenix 8 Solar, Fenix 8 AMOLED, Tactix 8 AMOLED, Enduro 3, Quatix 8, and Fenix E models. As usual, the rollout covers all available case sizes across these devices.
This firmware is not being pushed automatically over the air. Users who want to install Garmin software version 23.12 need to start the update manually from the watch’s settings menu. The watch must be connected through Bluetooth or Wi-Fi for the installation process to begin.
Because this is a beta update, Garmin users should install it with caution. Beta firmware can include unresolved bugs, and in this case, two important features are temporarily disabled after installation: ECG functionality and diving features. Anyone who relies on either of these tools may want to wait for a stable public release instead.
The changelog for Garmin firmware 23.12 is short, especially compared with version 23.11, which arrived shortly before it and introduced more noticeable features and control improvements. Version 23.12 is primarily a maintenance release designed to polish the user experience rather than add major new functions.
One of the most important fixes in this update addresses treadmill calibration. Some users experienced an issue where calibrating treadmill workouts did not properly improve distance and pace accuracy. With the new firmware, the watch should now make better use of treadmill calibration data.
After completing a sufficiently long treadmill workout, users can enter the distance shown on the treadmill. The watch then uses that information to improve future indoor running estimates. With version 23.12, this process should now work more reliably, helping athletes get more accurate pace and distance readings when training indoors.
For Garmin Fenix 8 owners who frequently run on a treadmill, this could be a useful update despite the limited changelog. However, users who need ECG or diving functions should think carefully before installing the beta version.
Garmin’s latest beta firmware shows that the company is continuing to refine its high-end smartwatch platform with smaller but meaningful improvements. While version 23.12 is not a headline-grabbing release, better treadmill calibration and general bug fixes can still make a noticeable difference for users who depend on accurate fitness tracking every day.
