new CORE 2 body temperature sensor
Update: New Core 2 Review, a detailed look is now live
CORE 2 is an upgraded real-time thermal monitoring device 48% smaller and 30% lighter than its predecessor, CORE 1. It features a redesigned modular attachment system, including a detachable clip. The new CORE 2 body temperature sensor is more compact and promises enhanced features.
The updated design addresses clip breakage issues, making the device easier to secure and charge. Additionally, a new LED indicator provides clear information on device status, battery life, and charging progress, resolving previous challenges in determining when the CORE was ready.
Despite introducing a USB-C connector on the energy supply side, CORE 2 remains compatible with the CORE 1 magnetic charger. A software update will be released for both CORE 1 and CORE 2 users ahead of CORE 2’s launch in late March 2025.
CORE 2 retains the same price as CORE 1 while delivering significant design, usability, and functionality improvements.
Recent Ecosystem Changes
CORE recently added significant new functionalities to its ecosystem, including a HEAT STRAIN INDEX, TEMPERATURE TRAINING ZONES and measures to indicate HEAT ADAPTATION.
The CORE CIQ App for Garmin has also continually improved; for example, it now includes heat strain index information in the FIT file for Garmin Connect.
CORE 2 Full specs
Final production specs may vary slightly.
- Dimensions (without clip): 41.9 x 29.4 x 7.1 mm
- Dimensions with clip: 45.1 x 32.6 x 9.6 mm
- Device weight: 8.6 g (without clip) | 11.4 g (with clip)
- Battery: Rechargeable lithium polymer cell (3.6V)
- Power Supply: USB-C magnetic adapter cable (included)
- Supply rating: 5V DC, max. 30mA current draw
- Battery Life: at least 6 days; up to 30 days with standby mode enabled
- Connectivity: Bluetooth low energy (BLE), ANT+ (2.4 GHz band)
- Max transmit power: 8 dBm (6.3 mW)
- Materials Description: Skin-compatible ABS (device) and TPU (elastic clip)
- Immersion Resistance: >1.5m water column for >6 hours
Device Temperature Ranges:
- Operation: 10°C – 45°C (device temperature)
- Absolute limits*: -20°C – 65°C (device temperature)
- Storage: 10°C – 25°C (recommended)
Measurement Ranges:
- Core Temperature: 36.0°C – 42.0°C
- Skin Temperature: 0°C – 50°C
Initial Thoughts
Buy (March, 2025)
the core sensor is easily, hands down the worst training product i have ever purchased. $250 for a device that you cannot tell is working / paired, one that burns through battery when it’s sitting on the shelf to the point where every 3rd or 4th activity you’re greeted with a dead battery, a clip that almost never stays attached in the place you put it, on and on. and all of this for metrics to tell you you went from 100.1 degrees to 100.4 during training. wow, great
Thanks for the info. I was tempted to try one as I want to do some heat adaption from a warm-weather race I’m doing this year. Until recently, I didn’t know that Garmin’s heat adaption is effectively useless unless you ride outside, as it uses your GPS location to get weather data. I was hoping that Core would be more useful. Seems like it’s not worth it.
@Matthew, yes my understanding about Garmin’s heat adaptation is that it is effectively useless for the reason you say (I asked CORE who wouldn’t comment on that) and also because even if the weather forecast is correct it doesn’t tell you yoru temperature, it is YOUR temperature that I understand is what links to the adaptation.
i think core is only worth it if you can get hot in hot conditions. Personally I find it hard to motivate myself to do that which is a shame as there are material gains to be had in exchange for the suffering
@Indy, yes to a degree! Later firmware (updatable) via the app improve battery management.
I found the clip generally ok until recently when the black retaining pin seems to often come out. clearly CORE is aware of these two issues, both seemingly addressed in the new product (March)
if the metrics, when paired with a HRM, only show that change then you wont get heat adaptation
First, I live in Phoenix Arizona in the USA. In the summer, day time temps are 40-45C…so it’s hot. I have been using Core since it first came out. I have paired it with various Garmin head units over the years. I have had a few problems in the past but the customer service team has been quick to respond. But overall, I am happy with the device. I use it to protect me from myself. When I see my core body temp has hit 103F, I make sure I am headed home. For me, it does what I want…I keep it simple.