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Garmin Index S2 Smart Scale Review

Donald Buraglio 01/13/2021
Donald Buraglio 01/13/2021
20K
Our reviews are 100% organic. We do not accept payment for reviews or bundle with advertising budgets. In most cases, the brand is providing the product to our reviewers free of charge.

January is the month we hold ourselves accountable for those New Year’s goals, and appropriate (read: not obsessive) use of a scale is one of the best tools to keep you on track. When the original Garmin Index scale debuted about five years ago, it was somewhat revolutionary in its ability to transmit and synchronize data in the Garmin Connect app, allowing dedicated Garmin users to combine accurate physiological metrics with performance data from the watch for a more comprehensive overview in the app.

Index S2 on top, original Index on bottom,

All of that synchronicity still happens with the Index S2, but the device itself isn’t quite as revolutionary this time around – rather, it includes a handful of pleasant display updates and advanced sensors for improved accuracy. It’s all included in a much sleeker package that weighs 30% lighter and has a noticeably smaller footprint than the original version.

Out of the box, complete setup of the scale takes 5-10 minutes, depending on whether the device needs a software update. Otherwise, the process is as simple as inserting the included batteries, selecting your weight units, pairing it with your smart phone, and allowing it to connect with your wifi network. After the initial setup, the S2 will detect and install updates automatically after your weigh-in. You can program up to 16 different users on the device, in case your whole family uses the same scale, or for small coaching groups to do regular weigh-ins on the same device.

Multiple user ID options

Tapping the scale with your foot activates it for use and stepping on the scale barefoot enables the full range of metrics to be measured. There’s no change in the metrics that are actually measured on the S2 from the original model, but the color display is much crisper. One cool new feature of the display is a trend line of weight data from the previous days for a quick assessment of what direction you’re heading. Previously, when you stood on the scale and waited for data to be synced to Garmin Connect, you had to open the app on your phone to see your trend lines. While this all still happens in the app – and trend lines can be extended out to 1 year – having a quick view of your 30-day trend gives you a nice snapshot of your recent progress (or lack thereof). The trend line display only happens with the weight metric—all of the other metrics have a single value display, but all include trends in the app like usual.

Weight trend over time

Another addition to the weight display is the difference between current and previous weight. This seems most useful for runners who are trying to figure out their hydration needs during a run, by weighing themselves before and after a workout to determine how much water weight is lost. A downside to this new feature is that it has the potential to be somewhat discouraging in regards to normal daily fluctuations in your weight, but the good news is that the “difference” number is kind of small, so it’s easy to ignore.

Garmin reports that the sensors in the Index S2 are more sensitive, and the algorithms based on those sensor readings have been refined. We can’t verify the accuracy of the sensors from one scale to the other, but we did notice a slight shift in values when stepping back and forth from the original Index to the S2. The differences are very small, within a few tenths of a pound for weight, and within one or two percent for the other metrics, which are all based on electro-impedance that sometimes has reliability issues based on the nature of the assessment.

Weight
Body fat percentage
BMI

One area we’d like to see further developed is some kind of frame of reference when it comes to various metrics; for example, if your bone mass is 11.0, what exactly does that mean? Is it healthy, or too low? Garmin shies away from any guidance in these areas because there is so much variability in “normal” values within the population, but it seems like some wide parameters could be offered based on information already in Garmin Connect such as gender, age, weight, activity level, etc. This could help users become more informed and attentive about things they can do aside from regular diet and exercise to improve their overall health, which should be the point of using a scale in the first place.

The Garmin Index S2 Smart Scale is available at www.buy.garmin.com.

Basic summary: An update to Garmin’s Index Smart Scale, which measures a number of physiological metrics in addition to basic weight. The S2 is smaller and lighter than the previous model, with a new color display and improved sensors for increased accuracy. The scale syncs with Garmin Connect via wifi, so your data is automatically stored and tracked in the app to interface with activity data from your Garmin watch.

MSRP: $150

Specs and Features:

  • Dimensions: 12.6” x 12.2” x 1.1” (320 x 310 x 28 mm)
  • Weight: 4.4 lbs (2.0 kg)
  • Battery life: Up to 9 months, uses 4 AAA batteries (included)
  • Weight limit: 400 lbs (181.4 kg)
  • Metrics: weight, body mass index (BMI), % body fat, body water %, skeletal muscle mass, bone mass
  • Weather widget
  • Color display screen with 30-day weight trendline graph
  • Previous weigh-in vs current weigh-in display
  • Supports up to 16 users
  • 2 color options – black or white
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Donald Buraglio

Donald is a physical therapist, California native, barefoot aficionado, and father of three with more than 25 years of experience in endurance sports. He was a collegiate rower at UCLA, then dabbled in marathons and Ironman-distance triathlons before falling in love with ultras in the early 2000s. His favorite locations to run include Marin County, CA, and the Sierra Nevada mountains, and he loves exploring America's National Parks. When he's not training for ultramarathons, he enjoys hiking or slacklining with his family in Monterey County, CA.

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