How Does A Smartwatch Measure Your Heart Rate And 4 Ways To Get Accurate Result

Are you curious to know how smartwatches measure your heart rate and how you can get accurate results from them?

In a smartwatch, you can find many features, but heart rate monitoring is one that draws a lot of attention.

Nowadays, hundreds of smartwatch brands are offering smartwatches that claim to measure heart rate accurately.

However, the question remains, are they capable of doing this, and if so, how?

Therefore, in this particular article, I will explain how smartwatches measure heart rate.

How Does A Smartwatch Measure Your Heart Rate

Heart rate monitoring is an essential feature in a smartwatch; smartwatches have a photoplethysmography (PPG) sensor to measure it.

You will see this sensor from low budget smartwatches to the premium Apple Watch, and all smartwatches use this same technology for heart rate monitoring.

You must have noticed the backside of smartwatches; here, you can see a raised area that houses some sensors, one of these sensors monitors your heart rate.

Smartwatch Backside with Sensors

When you monitor the heart rate by wearing these smartwatches on your wrist, the PPG sensor produces green light that enters your skin.

Since red color tends to absorb green and when green light enters the skin, they are absorbed by the blood.

Let me tell you that the heart beats periodically, which also affects the blood flow, and due to this, there is also a change in the amount of light absorbed.

And thus, by measuring the amount of these green lights detected by the sensors, these smartwatches provide you with a heart rate.

Heart Rate Monitoring Process

But now the question is, does this technique give you accurate results?

No, in this technique, you do not get accurate results because when the sensor detects the green light, its quantity is very low, and these sensors cannot measure it accurately.

So when you monitor the heart rate on both hands through one of your smartwatches, you can get different data.

So keep in mind that the data from the heart rate monitor of the smartwatch is inaccurate, and you should not rely only on it but use it to get ideas.

How To Monitor Heart Rate On Your Smartwatch

The ways of monitoring your heart rate may also differ on different smartwatches, but most budget smartwatches use the same method for monitoring your heart rate.

Most smartwatches have dedicated widgets to monitor heart rate; navigate to them.

Another way to monitor heart rate is through the menu section.

Every smartwatch has a dedicated section for heart rate monitoring in its menu section, as you can see in the menu section of this Fire-Boltt Visionary smartwatch.

Fire-Boltt Visionary Menu

And with this, you will start monitoring your heart rate.

How To Analyze Heart Rate Data

As much as you need to monitor your heart rate, it is equally important to analyze it correctly.

I find it interesting that smartwatches allow you to analyze all the data through their companion app after heart rate monitoring.

We do monitor heart rate but do not analyze its data deeply, and you should keep on analyzing your data.

4 Simple Tricks To Get Accurate Heart Rate

Admittedly heart rate monitoring is one of the most useful features of smartwatches.

Still, we cannot deny that most smartwatches fail to provide accurate heart rates, especially low-budget smartwatches.

Having said that, there are some tricks that you can use to get a more accurate heart rate from any smartwatch after trying them.

Let’s talk about them.

1. Test On Your Soft Part

Test On Your Soft Part

Do you know why the heart rate is tested on the soft part of the body?

It is because the LED lights can make better contact with the blood on the softer parts, making it easier to detect an accurate heartbeat.

So when you wear a smartwatch on your wrist, the green light emitted from the PPG sensor is not detectable by the sensor because of the wrist bones, and as a result, the result is received inaccurately.

Therefore, while monitoring the heart rate, try to wear the smartwatch on a delicate part, such as the lower part of the wrist.

2. Test On Clear Skin

Test On Clear Skin

You might be surprised to know this, but skin color can also affect the technology used in smartwatches for heart rate monitoring.

Yes, heart rate monitors’ data on clean skin and skin stained with tattoos may be different.

Therefore, as far as possible, monitor the heart rate on clean skin only.

3. Tighten The Straps

Tighten The Straps

Some people are fond of wearing loose watches, and they do so with traditional watches and smartwatches.

See, as long as the sensors on the back of the smartwatch don’t touch your skin, they won’t be able to send light into the skin, which will not give accurate heart rate monitoring.

Therefore, fasten the straps tightly and help the sensor detect the lights.

4. Buy A Good Smartwatch

Buy A Good Smartwatch

Often people buy Inexpensive smartwatches to save money, but when it comes to essential features like heart rate monitoring, you should go for a good smartwatch.

Cheap smartwatches do not use good quality sensors for cost-cutting, due to which they do not provide you with accurate heart rates.

In contrast, premium smartwatches like the Apple Watch are expensive but provide high-quality sensors that give you accurate heart rate data.

So if you are serious about heart rate monitoring, choose a good smartwatch.

But if you have low budget, check out these budget guides:


How Smartwatches Measure Heart Rate?

Smartwatches use a PPG sensor to measure heart rate; this sensor sends a green light to your skin so that some of the light is absorbed by the blood and the rest of the light is detected by the sensors; smartwatches give your heart rate by the amount of these detected lights.

Why Do Smartwatches Have Green Lights?

Blood is red, and red tends to absorb green the most, so green lights are used in PPG sensors to get accurate results from the light emitted.

Photo of author

Amit Chopra

Amit is a tech enthusiast who created this blog to pursue his keen interest in Wearable Technology. This blog contains reviews and guides to help you shop for the best product for you. He uses Fire-Boltt Visionary and OnePlus Nord Buds.