Amazfit
Pick Amazfit if
- Daily-wear watch under a budget
- 24/7 stress is the metric you care about most
- You don't want a chest strap
Amazfit vs Polar
Amazfit reads 15/27 signals from a wrist-only consumer watch and adds 24/7 stress. Polar reads 17/27, brings chest-strap-grade HRV under hard intervals (with H10), the ANS Charge recovery model, training load, plus an Aria-class scale ecosystem.
Amazfit
15/27API signals exposed
Zepp OS watch · partner API
vs
POLAR
17/27API signals exposed
Sport watch / chest strap
QUICK VERDICT
If you train by HRV under hard intervals or follow Polar's recovery and training load model, the chest strap is more accurate than any wrist-optical signal Amazfit can produce — and Polar's signal count is higher overall. If you want a consumer-friendly daily-wear watch at half the price with 24/7 stress baked in, Amazfit is the simpler choice. The two don't overlap as much as the signal counts suggest.
COVERAGE BY CATEGORY
Where each brand actually wins
Per-category breakdown of API signals.
SIGNAL BY SIGNAL
The full matrix
| Signal | Amazfit | Polar |
|---|---|---|
| Heart & Vitals | ||
| Resting HR | ✓ | ✓ |
| HRV | ✓ | ✓ |
| SpO2 | ✓ | ✓ |
| Respiratory Rate | ✓ | ✓ |
| Skin Temperature | — | ✓ |
| Body Temperature | — | — |
| Blood Pressure | — | — |
| ECG · AFib | — | — |
| Sleep | ||
| Sleep duration | ✓ | ✓ |
| Sleep stages | ✓ | ✓ |
| Sleep score | ✓ | ✓ |
| Activity | ||
| Steps | ✓ | ✓ |
| Active minutes | ✓ | ✓ |
| Calories | ✓ | ✓ |
| Activities | ✓ | ✓ |
| Floors climbed | — | — |
| Distance | ✓ | ✓ |
| Fitness & Recovery | ||
| VO2max | ✓ | ✓ |
| Training load | — | ✓ |
| Recovery / Readiness | ✓ | ✓ |
| Body Battery | — | — |
| Stress (continuous) | ✓ | — |
| Cardiovascular age | — | — |
| Body Composition | ||
| Weight | — | ✓ |
| Body fat % | — | — |
| Muscle mass | — | — |
| Hydration | — | — |
Verified against vendor developer documentation.
WHICH ONE FOR YOU
Pick the one that matches your priority
POLAR
Pick Polar if
- You train by HRV under hard intervals
- Chest strap during structured sessions is acceptable
- Recovery (ANS Charge) and training load drive your week
Amazfit+POLAR
Pick both if
- Polar H10 chest strap for structured sessions
- Amazfit for daily wear and 24/7 stress baseline
- Combined feed reaches 18/27 unique signals
FAQ
Frequently asked questions
Can I connect both Amazfit and Polar to MyBodyAI?
Yes. MyBodyAI merges signals from every connected source and uses richer-source-wins per field. Amazfit is built, waiting for vendor app approval, Polar is live via OAuth.
Which one covers more MyBodyAI signals?
Amazfit reads 15 of 27 tracked signals. Polar reads 17. The matrix above breaks the count down by category — they often win different categories.
Do the affiliate links change which device you recommend?
No. Recommendations on this page come from signal coverage and developer-API capability. Affiliate commissions never change the matrix, the pick-X-if cards, or your MyBodyAI subscription price.
What happens if I switch from Amazfit to Polar later?
Your MyBodyAI history is preserved per signal. New data starts arriving from Polar the moment you connect it. Disconnecting Amazfit pauses the old feed without deleting past data.
WHERE TO BUY
Check prices at the source
Direct links to each vendor's store. Some are affiliate.
- Amazfit Official store Check at Amazfit →
- Amazfit Official store Amazfit →
- POLAR Official store Check at Polar →
MORE COMPARISONS
Explore other pairs
OPTIONAL — IF YOU WANT MORE
Want one place that merges both feeds?
MyBodyAI merges these signals into Biological Age, Recovery and 9 other indices.
Try MyBodyAI free →