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Head-to-head

Garmin - Fenix 8 (47mm) vs Samsung - Galaxy Watch 7 (40mm)

Last updated · How Mars Score works
Fenix 8 (47mm)GARMINILLUSTRATION
Probe A
Garmin
Fenix 8 (47mm)
71.9/ 100B
Health & Fitness95· 32%
Battery & Connectivity70· 30%
Display57· 22%
Design45· 16%
Galaxy Watch 7 (40mm)SAMSUNGILLUSTRATION
Probe B
Samsung
Galaxy Watch 7 (40mm)
69.6/ 100B
Health & Fitness95· 32%
Battery & Connectivity38· 30%
Display51· 22%
Design91· 16%
The fork

Where they actually differ

The most decisive specs, ranked by how much they matter — before the full spec table.

SpecGarmin - Fenix 8 (47mm)Samsung - Galaxy Watch 7 (40mm)
Battery life384 h30 h
Peak brightness1000 nits3000 nits
Weight73 g28.8 g
Display size1.4 "1.31 "
Water resistance10 ATM5 ATM
Cellularfalsetrue
Quick verdict

Between the Fenix 8 (47mm) and Galaxy Watch 7 (40mm), the Fenix 8 (47mm) comes out ahead in battery life / display size, while the Galaxy Watch 7 (40mm) wins on peak brightness / weight. Overall, the Fenix 8 (47mm) scores 71.9 and the Galaxy Watch 7 (40mm) scores 69.6 on our Mars Score.

Buying advice

Which should you buy?

These two are nearly even on the Mars Score (71.9 vs 69.6). The decision is not about overall quality — both clear the bar — it is about which specific trade-offs fit your use.

Pick the Fenix 8 (47mm) if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. The biggest gaps in its favor are battery life, display size, water resistance. The single most decisive one: Battery life — 1180.00% more. 384 h vs 30 h.

Pick the Galaxy Watch 7 (40mm) if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are peak brightness, weight, cellular. The single most decisive one: Peak brightness — 200.00% more. 3000 nits vs 1000 nits.

Both ship with comparable ecg, spo2, so those specs do not separate the two — focus on the differences below.

Bottom line: there is no wrong answer here — match the spec advantages to how you actually use the product. The Mars Score parity says both are well-rounded; the differences are about trade-offs, not quality.

Decision guide

Which should you buy: Garmin - Fenix 8 (47mm) or Samsung - Galaxy Watch 7 (40mm)?

Garmin - Fenix 8 (47mm) leads the current Mars Score by 2.3 points.The more useful decision is the trade-off behind that result: compare display size, battery life against the way you will actually use the product.

Choose Garmin - Fenix 8 (47mm) if…

Garmin - Fenix 8 (47mm) has the measurable edge on battery life h, display size in, water resistance atm.

Choose Samsung - Galaxy Watch 7 (40mm) if…

Samsung - Galaxy Watch 7 (40mm) has the measurable edge on peak brightness nits, weight g, has cellular.

This is a structured comparison of the published catalog values. It is not a claim of identical real-world performance across every workload; use the linked spec drill-downs and methodology page to inspect the inputs.

Why Garmin - Fenix 8 (47mm) wins

  • Battery life — 1180.00% more. 384 h vs 30 h.
  • Display size — 6.87% more. 1.4 " vs 1.31 ".
  • Water resistance — 5.00 ATM more. 10 vs 5.

Why Samsung - Galaxy Watch 7 (40mm) wins

  • Peak brightness — 200.00% more. 3000 nits vs 1000 nits.
  • Weight — 44.20 g less. 28.8 vs 73.
  • Has Cellular.
Full readout

Spec comparison

Design

SpecGarmin - Fenix 8 (47mm)Samsung - Galaxy Watch 7 (40mm)
Case size47 mmlead40 mm
Weight73 g28.8 glead
Case materialfiber-reinforced polymeraluminum
Water resistance10 ATMlead5 ATM

Display

SpecGarmin - Fenix 8 (47mm)Samsung - Galaxy Watch 7 (40mm)
Display size1.4 "lead1.31 "
Always-on displaytruetrue
Peak brightness1000 nits3000 nitslead

Health & Fitness

SpecGarmin - Fenix 8 (47mm)Samsung - Galaxy Watch 7 (40mm)
ECGtruetrue
SpO2truetrue
Temperature sensortruetrue
Sleep trackingtruetrue
Blood pressurefalsetruelead

Battery & Connectivity

SpecGarmin - Fenix 8 (47mm)Samsung - Galaxy Watch 7 (40mm)
Battery life384 hlead30 h
GPStruetrue
Cellularfalsetruelead
NFCtruetrue
OSGarmin OSleadWearOS
Reader questions

Frequently asked

Which has longer battery life, Fenix 8 (47mm) or Galaxy Watch 7 (40mm)?+

Fenix 8 (47mm) lasts 384 hours vs 30 hours.

Do Fenix 8 (47mm) or Galaxy Watch 7 (40mm) support ECG?+

Both support ECG.

Which has cellular, Fenix 8 (47mm) or Galaxy Watch 7 (40mm)?+

Galaxy Watch 7 (40mm) offers a cellular variant; Fenix 8 (47mm) is Wi-Fi only.

Drill down

Spec-level deep dives

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