Polar H9 Heart Rate Sensor

Verdict: Polar's budget chest strap with the same electrode accuracy as the H10 — the right strap for 80% of athletes who own none.

Specs that matter

What you get

• H10-grade accuracy — same electrode pickup for cardio work
• Dual BLE + ANT+ — rare at this price; matches Garmin HRM-Dual
• Long battery — 12-18 months of regular training per cell

What you give up

• No internal memory — can't store swim HR (the H10 can)
• Single Bluetooth connection — can't stream to a watch and Zwift over BLE at once

Buy it if you cycle, run, or do Z2 cardio and want strap data without a sub. Skip it if you need swim HR (get the H10) or hate chest straps (Verity Sense armband).

Gilgen-Ammann et al. (2019, Eur J Appl Physiol) validated the H10 as research-grade against ECG; the H9 shares the same electrode geometry per Polar's spec.