fitbit
Pick Fitbit if
- Simplicity over data depth
- Google ecosystem and one-click OAuth
- ECG + AFib on the wrist matter
Fitbit vs Garmin
Fitbit aims for simplicity. Garmin aims for completeness. Fitbit Charge or Pixel Watch reads sleep, HRV, SpO2, VO2max, ECG out of the box. Garmin watches add Body Battery, 24/7 stress, training load — Garmin's OAuth API is not open to us yet, so you upload a GDPR export until then.
fitbit
16/27API signals exposed
Daily-wear watch + scale
vs
GARMIN
20/27API signals exposed
Athletic / outdoor watch
QUICK VERDICT
If clarity matters more than data depth, Fitbit. If you want every signal MyBodyAI can read from a single device, Garmin — even with manual upload until Garmin's OAuth API opens to us. Among MyBodyAI's currently-connected providers, Garmin is the only one delivering 24/7 stress and Body Battery — two signals MyBodyAI uses heavily in the autonomic balance and morning energy indices. (Oura and Amazfit also expose stress in their APIs, but those integrations are still pending vendor approval.)
COVERAGE BY CATEGORY
Where each brand actually wins
Per-category breakdown of API signals.
SIGNAL BY SIGNAL
The full matrix
| Signal | Fitbit | Garmin |
|---|---|---|
| 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
GARMIN
Pick Garmin if
- Body Battery and 24/7 stress matter
- You're fine uploading a GDPR ZIP weekly until OAuth opens
- Multi-week battery life and outdoor GPS
fitbit+GARMIN
Pick both if
- Garmin watch for the full signal stack
- Withings scale for body fat + body composition
- Once Garmin OAuth opens, Fitbit becomes optional
FAQ
Frequently asked questions
Should I choose Fitbit or Garmin?
For most people it is one or the other. Both are daily-wear devices that track the same core things, heart rate, sleep and activity, so wearing both is redundant. Use the matrix above to pick the one that wins the categories you care about.
Which one tracks more health signals?
Fitbit tracks 16 of the 27 signals I compare, Garmin tracks 20. The matrix above breaks it down by category, and they often win different categories.
Is it worth switching from Fitbit to Garmin?
Only if Garmin wins the categories you actually care about. If you already own Fitbit and it covers your main goal, the upgrade is rarely worth it. The matrix above shows exactly what changes.
How did you compare Fitbit and Garmin?
From each brand's official spec sheets and support pages, cross-checked against independent reviews like DC Rainmaker and The Quantified Scientist and peer-reviewed accuracy studies. Signal-level edge cases are noted in the matrix, not hidden behind a single check mark.
WHERE TO BUY
Check prices at the source
Direct links to each vendor's store. No affiliate links.
- fitbit Official store Check at Fitbit →
- GARMIN Official store Check at Garmin →
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 →