Best smart scale
Withings Body Smart
Withings smart scale that reads body composition through the feet, $129.95
$129.95
US price, checked
Smart scale
Garmin Index S2
Wi-Fi smart scale for up to 16 people with foot-to-foot body composition, $199.99
$199.99US price, checked
Check price at Garmin for Garmin Index S2 Our reviews rest on published sources, not hands-on testing. Our method
Porsche also cofounded Superhuman Chambers, which sells hyperbaric chambers · About the author. This is general information, not medical advice, and no clinician has reviewed it.
The verdict
Index S2 weighs you and estimates body fat, water, muscle and bone mass by passing a small current from foot to foot, then syncs to Garmin Connect. It suits you if you already use Garmin Connect or want one scale for a household. The catch: Garmin gives no accuracy figure, and no independent validation was found.
The trade-off
It costs $199.99, Garmin publishes no accuracy figure for the body composition readings, and every extra user needs a Garmin Connect account.
At a glanceSmart scale
- Body composition method
- Bioelectrical impedance
- Weighing
- Units: pounds, kilograms or stones and pounds…
- Profile inputs and modes
- Uses date of birth, gender, height and activity level from your Garmin Connect…
- Users
- Up to 16 people
Model reviewed: Index S2 Smart Scale, black (010-02294-02, also sold in white), Wi-Fi 2.4 GHz, four AAA batteries included
$199.99
Check price at Garmin US price, checked
No affiliate commission on this link. Check the exact variant before buying.
- Returns 30 days from receipt of a Garmin.com order. See conditions
- Warranty One year from the date of purchase. See conditions
About this price
List price for the black Index S2 (010-02294-02) on Garmin's US store, shown in US dollars on Oct 24, 2026. The white version (010-02294-03) was listed at the same amount. Garmin's page showed the scale in stock and shipping in 1 to 3 business days, with no sale price or crossed-out regular price. Bundles with the Index BPM blood pressure monitor were listed at $399.98 but weren't orderable, so they aren't counted. Garmin Connect+ is a separate optional plan and isn't included.Garmin says shipping is free on all Garmin.com orders.
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A GOOD FIT FOR
You want a Wi-Fi scale that syncs weight and body composition to Garmin Connect and can serve up to 16 people.
- You want weight and body composition trends from a Wi-Fi scale that syncs to Garmin Connect
- You want one scale for a household or team of up to 16 people, each with their own Garmin Connect account
- You want a battery-powered scale with a weight-only option and no charging cable
THINK TWICE IF
- You wear a pacemaker or another internal medical device: Garmin says not to use the scale
- You are or may be pregnant: Garmin says to consult your physician before using it
- You need body-fat accuracy that a study has confirmed, since Garmin gives no figure and no independent study was found
- You want fat and muscle readings for each arm and leg, which Garmin doesn't list for a scale with no handle
- You don't want every user to need a Garmin Connect account
What still needs checking
- Any accuracy figure or DEXA comparison for the Index S2. Garmin gives none on the pages checked, and a Europe PMC search on Oct 24, 2026 found no study that validated it
- The data behind Garmin's claim that its readings compare favorably with DEXA, since it comes from a forum reply that names no study or figure
- The frequency, electrodes and equations behind the readings, which Garmin doesn't publish
- Whether the weight-only option stops the current
- Whether the limit is 16 people in total or 16 besides the person who set up the scale, since Garmin words it both ways
- The weight display step, a weight tolerance and the display size and resolution
- What replacement AAA batteries cost, since Garmin doesn't price them
- Which phone operating system versions Garmin Connect needs for setup
- Who pays return shipping on a Garmin.com return
Is the Garmin Index S2 accurate?
Garmin gives no accuracy figure for its body composition readings. A Garmin staff forum reply says they compare favorably, on average, with DEXA and the Bod Pod, but it names no study or number4.
Independent tests of other consumer scales found body-fat errors of several kilograms against reference methods1213. None of those tests included the Index S2, and no independent study of it was found1213. Weight is the easier measurement: the scales in the French hospital study read within 0.3 kg of DEXA-measured weight at the median12.
Does the Garmin Index S2 need a subscription?
Not for the basics, per Garmin. Garmin said when it launched Garmin Connect+ that all existing features and data in Garmin Connect remain free7. None of the Index S2 pages checked mention a paid plan13.
Garmin Connect+ is optional and costs $6.99 a month or $69.99 a year8.
Can you use the Garmin Index S2 with a pacemaker?
Garmin says no. Its manual says the scale passes electric current through the user and should not be used by people with pacemakers or other internal medical devices2. The product page repeats the warning1.
Garmin also says to consult your physician before using the scale if you are or may be pregnant2. Its pages don’t say whether the weight-only option switches the current off12.
How many people can use the Garmin Index S2?
Garmin says up to 16 user profiles1. The manual says the person who set up the scale can invite up to 15 people. Each needs a Garmin Connect account and a connection to that person2.
The scale picks the user by weight and how often each person weighs in, so people of similar weight can be mixed up2.
The practical details.
| Exact variant | Index S2 Smart Scale, black (010-02294-02, also sold in white), Wi-Fi 2.4 GHz, four AAA batteries included |
|---|---|
| Body composition method | Bioelectrical impedance. A small current runs from one foot through the body to the other foot, and Garmin lists no handle or hand electrodes. The pages checked give no frequency or electrode count. It reports body mass index, body fat %, body water %, skeletal muscle mass and bone mass, plus a 30-day weight trend. Garmin says bone mass is calculated from your age and lean body mass |
| Weighing | Units: pounds, kilograms or stones and pounds, set with a switch on the underside. Maximum load 400 lb (181.4 kg). The pages checked give no display step or weight tolerance |
| Profile inputs and modes | Uses date of birth, gender, height and activity level from your Garmin Connect profile. An activity class of 8 to 10 turns on Athlete Mode, which Garmin's FAQ names when body fat reads lower than expected. With socks on, the scale records only weight and BMI. A weight-only option turns off the other body composition data |
| Users | Up to 16 people. The person who set up the scale invites up to 15 others in Garmin Connect. Each needs a Garmin Connect account and a connection to that person. Guest data isn't stored or synced. The scale tells users apart by weight and how often each person weighs in, so similar users can be mixed up |
| Connectivity and app | Wi-Fi (2.4 GHz) syncs readings to Garmin Connect, and the scale stores up to seven networks. Garmin's spec also lists Bluetooth LE and ANT. Setup and settings are in the Garmin Connect app. The pages checked give no minimum phone operating system |
| Battery | Four AAA alkaline batteries, included. Garmin says they last up to 9 months and tells you to use 1.5 V cells |
| Display | A high-resolution color display that steps through your readings every few seconds, plus a weather widget that needs Wi-Fi. Garmin doesn't state its size or resolution |
| In the box | Index S2, four AAA batteries, four carpet feet and documentation |
| Dimensions | 12.6 x 12.2 x 1.1 in (320 x 310 x 28 mm) and 4.4 lb (2.0 kg), per the specs tab of Garmin's product page. The maximum load is 400 lb (181.4 kg). |
| Materials | A glass surface, per Garmin's manual and support FAQ. Garmin says wearing shoes or heels can damage the glass. The product page offers black and white designs. Other materials are not stated by the manufacturer. |
Before you buy
InstallationNo installation beyond setup
No installation beyond setup. You pair the scale through the Garmin Connect app and connect it to a compatible Wi-Fi router. Garmin says you need both before you can use all its features. Garmin lists a 2.4 GHz Wi-Fi radio. The four AAA batteries are in the box, and so are four carpet feet for carpeted floors. Garmin recommends a hard, flat floor for the most accurate weight.
WarrantyOne year from the date of purchase, per Garmin's Consumer Limited Warranty
One year from the date of purchase, per Garmin's Consumer Limited Warranty. The terms, revised Dec 30, 2025, cover Garmin's non-aviation products and don't name the Index S2. Garmin chooses whether to repair it, replace it with a new or Garmin Recertified device, or refund the purchase price. The warranty excludes cosmetic damage, batteries unless a defect damaged the product, and damage from accident, abuse, misuse or water. You pay shipping to Garmin. A repaired or replacement device is covered for 90 days or the rest of the original year, whichever is longer. In the US, it covers only devices bought from Garmin or an authorized US reseller.
Returns30 days from receipt of a Garmin.com order, per Garmin's shipping and returns page
30 days from receipt of a Garmin.com order, per Garmin's shipping and returns page. The scale must be in its original condition, and you start the return online with a return request. Garmin says opened software, downloadable items and custom products can't be refunded. The page doesn't say who pays return shipping. Bought from another store, the scale goes back to that store under its own policy, and Garmin says restocking fees may apply.
More about this assessment
Index S2 is Garmin's Wi-Fi smart scale. It passes a small current from one foot to the other. It reports weight, BMI, body fat, body water, skeletal muscle mass and bone mass to the Garmin Connect app. Garmin lists it at $199.99 on its US store. Garmin publishes no accuracy figure for the body composition readings, and no independent validation study was found. Setup needs a phone with the Garmin Connect app, and each extra user needs their own Garmin Connect account. Garmin says people with a pacemaker or other internal medical device should not use it. Garmin's US Scales & Monitors page lists no other smart scale.
Strengths on paper
- Readings sync over Wi-Fi to Garmin Connect, where Garmin says they sit with your other wellness data
- Up to 16 people can use one scale, each with their own readings in Garmin Connect
- Four AAA batteries are included and last up to 9 months, according to Garmin
- A weight-only option turns off the other body composition data
- Garmin says existing Garmin Connect features stay free, and the paid Connect+ plan is optional
- Garmin's general warranty is 1 year, and Garmin.com orders have a 30-day return window
Limitations
- Garmin describes a current from one foot to the other and lists no handle, segmental readings or ECG
- Garmin gives no accuracy figure. A Garmin staff forum reply says only that the readings compare favorably, on average, with DEXA and the Bod Pod
- No independent validation of the Index S2's body composition was found
- Independent tests of other consumer scales found body-fat errors of several kilograms against reference methods, and none of them tested the Index S2
- Every extra user needs a Garmin Connect account and a connection to the person who set up the scale
- The scale picks the user by weight and weigh-in habit, so people of similar weight can be mixed up
- Socks on means weight and BMI only, and Garmin says to wait two hours after eating, drinking, exercising, bathing or a sauna
- Not for pacemakers or other internal medical devices, and Garmin's pages checked don't say whether the weight-only option switches the current off
Running costs.
PLAN YOUR OWNERSHIP COSTS
What will it cost to own?
Change the assumptions to fit your use. Leave an unknown cost blank. Add water, subscriptions, cleaning, shipping and taxes if they apply. Use average operating power, not the maximum rating.
3-year known subtotal
$199.99Incomplete: annual consumables, energy use. This is not the full ownership cost.
Energy component: Unknown
Purchase + installation + years × (annual consumables + annual other) + watts/1000 × hours/day × 365 × years × $/kWh. Annualized allowances, not an exact replacement schedule. Excludes taxes, shipping, finance and resale unless entered.Replacement parts & cost assumptions
Recorded recurring parts and refills:
- AAA alkaline batteries (four): price not stated, every 9 months. Garmin includes the first set and says they last up to 9 months. It doesn't price replacements. Garmin's warranty excludes batteries unless a defect damaged the product.
- Purchase is the $199.99 list price on Oct 24, 2026, before tax.
- Other annual costs are $0 because Garmin says its existing Garmin Connect features are free. Garmin said when it launched Garmin Connect+ in March 2025 that all existing features and data in Garmin Connect remain free. None of the Index S2 pages checked mention a paid plan. Connect+ is optional at $6.99 a month or $69.99 a year, which would add $209.97 over three years on the annual plan. That isn't counted.
- Annual consumables are unknown. The box has four AAA cells that Garmin says last up to 9 months, but Garmin doesn't price replacements. The scale is battery-powered, so energy use isn't counted.
- Installation is $0 because setup happens in the Garmin Connect app.
Evidence & sources.
Are smart scales worth it? Our evidence review grades the research as Moderate. That grade is about the claim, not about this product.
- Manufacturer claimPrice, specs, box contents, battery life, connectivity, the user limit and the setup steps come from Garmin's US product page, owner's manual and support FAQ. Garmin's US Scales & Monitors page lists the Index S2 as its one smart scale.139 Manufacturer information, not independent testing. The manual's footer reads March 2026, version 4, with a 2020 copyright line. The product page prints no accuracy figure.
- Regulator recordFDA's openFDA 510(k) data return one record with Garmin as applicant or in a device name: the Garmin ECG App (K221774, Jan 12, 2023). No scale record turned up, and Garmin's Index S2 page claims no FDA clearance.1011 A database search isn't proof that no listing exists. Garmin's manual says its BMI and body fat ranges are not intended to diagnose any medical condition.
- Manufacturer claimGarmin's manual says the scale passes electric current through the user and should not be used by people with pacemakers or other internal medical devices. It says to consult your physician before use if you are pregnant or think you may be. The product page repeats the warning for internal electronic devices.12 This is Garmin's own safety guidance, not a clinical finding. Garmin offers a weight-only option, but the pages checked don't say whether it stops the current.
- Manufacturer claimGarmin's product page has a heading that reads "Accuracy matters when it comes to your goals" but gives no figure. A Garmin staff reply in the Index S2 forum says the body composition metrics compare favorably, on average, with gold-standard methods such as DEXA and the Bod Pod. It also says the scale meets or exceeds standards for body weight scales. The reply names no study, figure or standard.14 This is a maker's claim, not independent testing. The forum reply is shown as over six years old. Garmin's support FAQ says its body metrics aren't meant to add up to your total weight.
- Published studyA 2021 observational study at a French hospital compared three consumer smart scales with DEXA in patients referred for a scan. They were the Tefal Body Partner, the Terraillon DietPack and the Withings Body Cardio. Median fat-mass errors were 2.2, 4.4 and 3.7 kg too low in 53, 52 and 48 patients. Median weight errors were 0.3 kg or less. The authors concluded that smart scales aren't accurate for body composition and shouldn't replace DEXA in patient care.12 The study didn't test the Index S2, so these figures don't describe it. They show how far other consumer scales sat from DEXA on fat mass, while their weight readings were close.
- Published studyA 2023 laboratory study of 73 healthy adults aged 19 to 50 compared 15 body-fat devices, 14 of them consumer-grade, with a four-compartment reference model. Average errors ranged from 3.5 percentage points too low to 11.7 points too high, and the standard error of the estimate ranged from 3.1 to 7.5 points. Repeat readings were consistent, with precision errors of 0.0 to 0.49 points.13 The paper doesn't name a Garmin device, so the figures don't describe the Index S2. A device can be consistent and still consistently wrong.
- Manufacturer claimGarmin Connect+ is an optional plan at $6.99 a month or $69.99 a year. Garmin said at its March 2025 launch that all existing features and data in Garmin Connect remain free.78 The launch statement is Garmin's. The Connect+ features Garmin lists don't mention scale readings, and none of the Index S2 pages checked mention a paid plan.
Sources (13)
- Index S2 Smart Scale Garmin · manufacturer · checked Oct 24, 2026
- Index S2 Smart Scale Owner's Manual Garmin · manufacturer · checked Oct 24, 2026
- Learn more about using the Index Smart Scale Garmin Support · manufacturer · checked Oct 24, 2026
- Garmin staff reply on Index S2 body fat accuracy, Garmin forums Garmin Forums · manufacturer · checked Oct 24, 2026
- Consumer Limited Warranty Garmin · manufacturer · checked Oct 24, 2026
- Shipping, Returns & Refunds Garmin · manufacturer · checked Oct 24, 2026
- Elevate your health and fitness goals with Garmin Connect+ Garmin (press release) · manufacturer · checked Oct 24, 2026
- Garmin Connect+ Garmin · manufacturer · checked Oct 24, 2026
- Smart Scales & Heart Rate Monitors Garmin · manufacturer · checked Oct 24, 2026
- openFDA 510(k) records for applicant Garmin U.S. Food and Drug Administration (openFDA) · regulator · data file · checked Oct 24, 2026
- openFDA 510(k) records with Garmin in the device name U.S. Food and Drug Administration (openFDA) · regulator · data file · checked Oct 24, 2026
- Accuracy of smart scales on weight and body composition: observational study JMIR mHealth and uHealth (Frija-Masson J et al.) · study · checked Oct 24, 2026
- Assessing the reliability and cross-sectional and longitudinal validity of fifteen bioelectrical impedance analysis devices British Journal of Nutrition (Siedler MR et al.) · study · checked Oct 24, 2026
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About this review. The facts on this page come from manufacturer pages, regulator records and published studies, checked Oct 24, 2026. The sources are listed above.
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