Pick Withings if
- Long-term body composition tracking
- Blood pressure or sleep apnea screening
- You prefer scale + BP monitor over a watch
Withings is medical-grade body composition, blood pressure, sleep apnea, AFib. Garmin is athletic 24/7 — Body Battery, stress, HRV, training load. They share the everyday heart, sleep and activity baseline, but each owns a different specialty — Withings the body, Garmin the training day.
Withings and Garmin are the most complementary live pair in MyBodyAI. Withings goes deepest on the body (muscle, water, visceral fat, BP, temperature, AFib, sleep apnea); Garmin reaches weight, body fat, bone mass, muscle mass and hydration through the Index S2 scale and stops there. Garmin owns the day (Body Battery, stress, sleep, HRV, activities). Combined they cover 33 of 33 tracked signals. They share the everyday heart, sleep and activity baseline, but each owns a different specialty — Withings the body, Garmin the training day.
Per-category breakdown of health signals exposed by each vendor's developer API. The number is breadth, not quality.
| Signal | Withings | Garmin |
|---|---|---|
| Heart & Vitals | ||
| Resting HR | ✓ | ✓ |
| HRV | ✓ | ✓ |
| SpO2 | ✓ | ✓ |
| Respiratory Rate | ✓ | ✓ |
| Skin Temperature | ✓ | ✓ |
| Body Temperature | ✓ via BeamO | — |
| Blood Pressure | ✓ via BPM Core | ✓ via Index BPM |
| ECG recording | ✓ | ✓ |
| AFib detection | ✓ | ✓ |
| Vascular age | ✓ via Body Scan 2 | — |
| Sleep | ||
| Sleep duration | ✓ | ✓ |
| Sleep stages | ✓ | ✓ |
| Sleep score | ✓ | ✓ |
| Sleep efficiency | ✓ | — |
| Sleep apnea index | ✓ | — |
| Activity | ||
| Steps | ✓ | ✓ |
| Active minutes | ✓ | ✓ |
| Calories | ✓ | ✓ |
| Activities | ✓ | ✓ |
| Floors climbed | ✓ | ✓ |
| Distance | ✓ | ✓ |
| Fitness & Recovery | ||
| VO2max | ✓ | ✓ |
| Training load | — | ✓ |
| Recovery / Readiness | — | ✓ |
| Body Battery | — | ✓ |
| Stress (continuous) | — | ✓ |
| Cardiovascular age | ✓ via Body Scan 2 | — |
| Body Composition | ||
| Weight | ✓ via Body Scan 2 | ✓ via Index S2 |
| Body fat % | ✓ via Body Scan 2 | ✓ via Index S2 |
| Muscle mass | ✓ via Body Scan 2 | ✓ via Index S2 |
| Hydration | ✓ via Body Scan 2 | ✓ via Index S2 |
| Bone mass | ✓ via Body Scan 2 | ✓ via Index S2 |
| Visceral fat | ✓ via Body Scan 2 | — |
Verified against vendor developer documentation and MyBodyAI backend code. This counts what a brand's API exposes, which is not the same question as what one device measures: the device catalog scores each model's own hardware, so its numbers differ.
Current Withings models Body Scan 2 (2026), BodyFit (2026), BPM Vision (2025), BeamO (2025), all 14 Withings devices
Current Garmin models CIRQA Smart Band (2026), Forerunner 170 (2026), Forerunner 70 (2026), Forerunner 570 (47mm) (2025), all 28 Garmin devices
Pick Withings if
Pick Garmin if
Pick both if
Yes, and they complement each other. Withings measures what a watch cannot on its own, body composition from a smart scale, blood pressure, and on some models an ECG. Many people keep Garmin for daily tracking and add a Withings device for the rest.
Withings tracks 29 of the 33 signals I compare, Garmin tracks 27. The matrix above breaks it down by category, and they often win different categories.
Start with whichever covers your main goal. For daily heart rate, sleep and workouts, go with Garmin. For weight, body composition and blood pressure, go with Withings. You can add the other later.
From each brand's official spec sheets and support pages, cross-checked against independent hands-on reviews (DC Rainmaker, the5krunner, Tom's Guide). Signal-level edge cases are noted in the matrix, not hidden behind a single check mark.
Links to each vendor's store. None of them changed any pick above.
MyBodyAI is what I build with these signals — it pulls from any combination of the brands above and derives Biological Age and 12 health indices from the raw numbers. Free to try, no card. It's optional — the comparison above stands on its own.
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