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Smart scales —
what works, and how

Any scale that writes to Apple Health will sync your weight and body fat. A few go further. Here’s exactly what you get from each route, so you can decide whether you need to buy anything at all.

You don’t need a smart scale. Body composition can be entered by hand on any tier, and a DEXA scan can be imported to calibrate everything. A scale just saves you the typing.

Three ways in

RouteWhat you getTierEffort
Withings account
Direct connection
Everything. Weight, body fat, lean mass, muscle mass, bone mass, water, visceral fat — plus segmental analysis (per-limb lean mass) where your scale measures it. All tiers Connect once, then automatic
Apple Health
Any scale that writes to it
Weight and body fat only. Apple Health doesn’t carry muscle mass, bone mass, visceral fat or water, so those can’t come through this route no matter what your scale measures. Core and above Enable once, then automatic
File import
XLSX or CSV export
Everything your scale records — up to 12 metrics, including the ones Apple Health drops. All tiers Manual, whenever you like
Type it in Whatever you choose to enter. All tiers Manual
The thing nobody tells you: no scale talks to Apple Health directly — its companion app is always the bridge, and Apple Health only carries weight and body fat percentage. If you want muscle mass, visceral fat and the rest flowing in automatically, that means Withings. For any other scale, use the file export.

Popular scales

ScaleBest routeFull metrics?Notes
Withings
Body Smart, Body+, Body Scan
Connect your Withings account Yes — all of them The only scale we sync directly. Wi-Fi, so readings arrive without opening an app. Body Scan adds segmental analysis.
Wyze
Scale X, Scale S
Export file, or Apple Health Yes — via export Cheap and accurate enough. Export from the Wyze app when you want the full picture; Apple Health covers weight and fat in between.
Renpho Apple Health Weight & body fat Widely owned and inexpensive. The extra metrics stay in the Renpho app.
Eufy
P2 Pro, P3
Apple Health Weight & body fat Good budget option; multi-user support is strong if a household shares one.
Garmin Index S2 Apple Health Weight & body fat Sensible if you already wear a Garmin.
Etekcity / FITINDEX Apple Health Weight & body fat Inexpensive, reliable weight tracking.
Fitbit Aria Apple Health Weight & body fat Discontinued hardware, and Fitbit’s partner API is being retired — not one to buy now.
Qardio Base Apple Health Weight & body fat Writes body fat to Apple Health natively, which not all do.
Tanita / Omron File export, or type it in Yes — via export Clinical-grade accuracy. App support varies by model; the export route is the reliable one.
Anything else Apple Health, or type it in Weight & body fat If its app writes to Apple Health, it works.

Why only Withings connects directly

A fair question, and the answer is simply that it’s the only consumer scale with an open developer API. Withings publishes one anyone can build against, which is how we pull your full history rather than just what Apple Health carries.

Aggregator services exist that would connect many more, but they cost several hundred dollars a month — which we’d have to pass on to you. Given Apple Health and file import already cover every scale, that isn’t a trade worth making.

Which should you buy?

If you want the full picture automatically — a Withings. It’s the only scale we connect to directly, and it's the only route that brings muscle mass, visceral fat, water and segmental data in without you doing anything.

If you already own a scale — keep it. Turn on Apple Health sharing in its app and your weight and body fat will flow in. Add a file export occasionally if you want the rest.

If you’re buying on a budget — a Wyze Scale X. The export route gives you everything, and it costs a fraction of a Withings.

Setting it up

Withings

Apple Health (any scale)

File import

Metric availability reflects what each route actually carries, checked against our own integrations. Scale manufacturers change their apps — if something here is out of date, email [email protected] and we’ll correct it.

Hemingway Performance is an informational tracking tool, not medical advice.