
Polar H9
Score: 83/100
Amazfit Active 2
Score: 83/100Rankings

The Polar H9 is a chest-mounted ECG heart-rate sensor offering exceptional accuracy and a 400-hour battery life. Its main trade-off is the lack of onboard storage and reliance on a replace-once coin cell battery. Ideal for athletes who need precise data across multiple sports and appreciate dual-protocol connectivity.

The Amazfit Active 2 Premium is a round stainless-steel smartwatch with a sapphire-protected AMOLED screen and 10-12 days of battery endurance. It lacks an included USB-C charger and can suffer intermittent Bluetooth drops. Best suited for style-conscious users who value premium materials and dual-frequency GPS.
| Attribute | ![]() | ![]() |
|---|---|---|
400 hoursbest | 240 hours | |
| ↓ lower better | 60 g | 31.65 gbest |
— | 1.32 inbest | |
— | 160best |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Battery & Power(2) | ||
Battery Life (hours) | 400 hours | 240 hours |
Battery Type | CR 2025 | Lithium-ion |
Build & Design(3) | ||
Weight (g) | 60 g | 31.65 g |
Water Resistance (IP Rating) | IP68 | 5 ATM |
Strap Material | Polyamide/Polyurethane/Elastane/Polyester | Leather, Silicone |
Connectivity(1) | ||
Bluetooth Version | Bluetooth LE | 5.3 |


Products in the top-left offer the best value (high score, low price).

Editors and CrossFit-focused reviewers consider the Polar H9 the best-value chest strap, emphasizing its precise ECG tracking, dual-protocol connectivity, and underwater capability.

Professional reviewers describe the Amazfit Active 2 Premium as delivering premium-grade features-speakers, microphone, offline maps and a high-brightness sapphire-protected display-at a budget-friendly $129 price. They commend its compact 44 mm round case, 5 ATM water resistance, precise BioTracker sensor and impressive 10-day battery life, while noting the missing USB-C charger and occasional Bluetooth hiccups as minor drawbacks.
Everyday users consistently praise the watch's comfortable fit, long battery endurance, stylish strap options and bright, readable display. The inclusion of offline maps and voice control is also well-received. Recurring complaints focus on Bluetooth stability issues and the absence of a charging cable in the box, with some noting modest audio quality.
“premium features without the premium price”

