Apple Watch Series 12 Heart Rate Test vs Garmin, Pixel Watch and More

Known for rigorous testing that pits smartwatches directly against gold-standard chest straps, Rob over at The Quantified Scientist has carried out a massive heart rate study examining how the Apple Watch Series 12 stacks up against Garmin, Google Pixel Watch, and other competitors.

For years, Apple has held a strong reputation for optical sensor performance. However, as competitors ramp up their sensor arrays and algorithms, fitness enthusiasts often question whether Apple still holds the crown or if dedicated endurance platforms like Garmin have closed the distance.

The testing evaluated data points across diverse scenarios, including steady-state cycling, outdoor running, indoor rowing, and daily living activities, comparing optical wrist readings against reference ECG chest monitors like the Polar H10.

The results of the analysis revealed that the Apple Watch Series 12 continues to lead the industry in optical heart rate monitoring precision. Across the vast majority of exercise tests, the device demonstrated a exceptionally high correlation with chest strap data, maintaining low root mean square error metrics even during rapid heart rate spikes.

While optical sensors typically struggle during activities with heavy wrist flexion, such as weightlifting or indoor rowing, the Apple Watch Series 12 managed to filter out motion artifacts far better than most competing wearables.

While hardcore athletes who need instant, split-second accuracy for high-intensity interval training will still benefit from wearing an external chest strap, the Apple Watch Series 12 remains the most reliable standalone wrist-based option on the market today. Check out the following YouTube video to learn more.