Heart Rate Ninja uses your heart rate monitor to measure your workout intensity.

Yes. Heart Rate Ninja uses your heart rate monitor to measure your workout intensity.

Yes! Heart Rate Ninja does not require any proprietary hardware.

Heart Rate Ninja is compatible with most popular Bluetooth LE heart rate monitors. Click here to learn more.

Unlike most heart rate monitors, the Apple Watch does not allow apps to access heart rate data via Bluetooth. We highly recommend a Bluetooth chest strap or armband heart rate monitor.

1. Make sure your monitor is turned on
2. Make sure you are wearing your monitor
3. Make sure your monitor is within 30' of your phone or tablet
4. Make sure your monitor is not paired with another app
5. Make sure your monitor is not paired with another device
6. Make sure your monitor's battery is charged and working
7. Make sure your monitor is Bluetooth LE compatible
8. Make sure your phone or tablet's Bluetooth is enabled
9. Make sure Heart Rate Ninja has Bluetooth access
10. Make sure Heart Rate Ninja has Location access
11. Restart your phone or tablet

"To estimate your maximum age-related heart rate, subtract your age from 220. For example, for a 50-year-old person, the estimated maximum age-related heart rate would be calculated as
220 – 50 years = 170 beats per minute (bpm)." cdc.gov

The max range will vary based on environmental obstructions (walls, workout equipment, etc.) between the app and your heart rate monitor(s) and the Bluetooth capabilities of your phone or tablet.

In a gym with a high number of obstructions we've seen a max distance of 30-50'. However, there are a number of steps you can take to make sure you achieve the highest distance.

The most important is to make sure there is an unobstructed line-of-sight from your phone/tablet to each heart rate monitor.

If you're coming from another heart rate monitoring app you should see the same range you saw in other apps (all apps communicate with the monitors in a similiar manner).

If you're having any issues related to range send us an email. We can help diagnose any issues and get you setup with a possible software-based solution.

The maximum number of heart rate monitors that can be connected depends on the Bluetooth capabilities of your phone or tablet.

We have had gyms run workouts with 25 monitors at the same time.

If you're unsure about the Bluetooth capabilities of your device request a demo and we'll give you a free trial so you can make sure Heart Rate Ninja works for your needs.