POLAR
Pick Polar if
- Endurance training is your priority
- You compete and need accurate workout HRV
- Recovery score and training load drive your week
Polar vs Withings
Polar reads HRV, recovery, and training load from the chest. Withings reads body composition, blood pressure, and sleep apnea screening from the bathroom and the bedroom.
POLAR
18/33signals its devices cover
Sport watch / chest strap
vs
withings
29/33signals its devices cover
Scale, BP monitor, watch
QUICK VERDICT
Polar is for the workout. Withings is for the rest of the day. Combined they fill very different gaps: Polar's RMSSD HRV during training, Withings' muscle mass and blood pressure trends week over week. Neither replaces the other — and neither is the right primary device on its own for someone training seriously and tracking long-term health.
COVERAGE BY CATEGORY
Where each brand actually wins
Per-category breakdown of health signals exposed by each vendor's developer API. The number is breadth, not quality.
SIGNAL BY SIGNAL
The full matrix
| Signal | Polar | Withings |
|---|---|---|
| Heart & Vitals | ||
| Resting HR | ✓ | ✓ |
| HRV | ✓ | ✓ |
| SpO2 | ✓ | ✓ |
| Respiratory Rate | ✓ | ✓ |
| Skin Temperature | ✓ | ✓ |
| Body Temperature | — | ✓ via BeamO |
| Blood Pressure | — | ✓ via BPM Core |
| 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 |
| Body fat % | — | ✓ via Body Scan 2 |
| Muscle mass | — | ✓ via Body Scan 2 |
| Hydration | — | ✓ via Body Scan 2 |
| Bone mass | — | ✓ via Body Scan 2 |
| 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 Polar models Street X (2026), Grit X2 (2025), Loop (2025), Grit X2 Pro (2024), all 11 Polar devices
Current Withings models Body Scan 2 (2026), BodyFit (2026), BPM Vision (2025), BeamO (2025), all 14 Withings devices
WHICH ONE FOR YOU
Pick the one that matches your priority
withings
Pick Withings if
- Long-term body composition matters
- Blood pressure or apnea screening matter
- You don't want anything strapped to your chest
POLAR+withings
Pick both if
- Polar chest strap during structured sessions
- Withings scale every morning, BP monitor weekly
- Most complementary pair across the live providers
FAQ
Frequently asked questions
Can I use Polar and Withings together?
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 Polar for daily tracking and add a Withings device for the rest.
Which one tracks more health signals?
Polar tracks 18 of the 33 signals I compare, Withings tracks 29. The matrix above breaks it down by category, and they often win different categories.
Which one should I get first?
Start with whichever covers your main goal. For daily heart rate, sleep and workouts, go with Polar. For weight, body composition and blood pressure, go with Withings. You can add the other later.
How did you compare Polar and Withings?
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.
WHERE TO BUY
Check prices at the source
Links to each vendor's store. None of them changed any pick above.
MORE COMPARISONS
Explore other pairs
OPTIONAL — IF YOU WANT MORE
Want one place that merges both feeds?
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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