How Does A Smartwatch Measure Your SpO2 (And Get Accurate Result)

In this blog, I will tell you about the process of measuring the Spo2 of smartwatches in a complete way.

Spo2 monitoring feature is common these days but was difficult in earlier smartwatches; you used to see only features like heart rate monitoring.

But after, the demand for Spo2 increased significantly due to diseases like Covid-19, which led to a lack of oxygen in the blood.

Spo2, i.e. blood oxygen level, shows the amount of oxygen in your blood.

As per the Healthline report, 95% or higher is considered good, and less than 90% oxygen level is regarded as a medical emergency.

So, in this blog, I will explain how a smartwatch measures your Spo2 level.

How Does A Smartwatch Measure Your SpO2?

Smartwatches use Reflectance Oximetry technology to measure Spo2; in this technique, Red and Infrared light (IR) is projected into your wrist.

This red light enters your oxygen-contained blood tissues, and the lights are detected back by sensors used in smartwatches.

The Spo2 level is shown to you based on the difference between the light sent and detected by the smartwatch.

This technique is very similar to heart rate monitoring, but red and infrared lights are used instead of green.

How To Monitor Spo2 On Any Smartwatch?

You get to see dedicated sections for monitoring Spo2 in smartwatches.

Most budget smartwatches provide dedicated options for spo2 monitoring in the widget section.

Apart from this, you can also perform Spo2 monitoring by going to the menu section of the smartwatch.

For this, you just have to go to the Spo2 option and tap on it, and in a few seconds, the result will be in front of you.

How To Get Accurate Spo2 On Smartwatches?

There is no guarantee that smartwatches will provide you with accurate Spo2 data; they are not medical devices, so they use their data only for ideas and not for medical purposes.

But is there any way to get accurate Spo2 data from any smartwatch?

I have been using smartwatches for the past several years, and during this time, I have found some ways which prove to be effective in order to getting accurate Spo2.

Dedicated Sensors

Most budget smartwatches do not have dedicated Spo2 sensors, but they provide Spo2 levels from heart rate sensors, which are unreliable.

However, due to the increasing demand for the Spo2 feature, smartwatch brands have done a lot of work on it.

Nowadays, you get to see dedicated Spo2 sensors even in low-budget smartwatches capable of providing better results.

So to get accurate Spo2 from any smartwatch, it is necessary to have a dedicated Spo2 sensor.

Test On Soft Part

If you have done Spo2 monitoring with an oximeter, you will know that the oximeter is worn on the finger because the finger part is soft enough so that the sensor’s light can easily reach the blood.

When we wear a smartwatch, the sensors are on our wrist, and the wrist part is not that soft due to being wrist bone.

Therefore, during Spo2 monitoring, you will get better results by wearing the smartwatch on the lower part of the wrist.

Use Premium Smartwatches

The easiest way to get accurate Spo2 from smartwatches is to go for premium smartwatches like Apple Watch.

It is because premium sensors are used in these smartwatches, whereas you do not get to see best sensors in low-budget smartwatches.

How To Measure Smartwatch’s SpO2 Sensor Accuracy?

Whenever you monitor Spo2 with your smartwatch, you must have a question about its accuracy.

But I am going to tell you how you can measure its accuracy.

The easiest way to measure the accuracy of the Spo2 level reported by a smartwatch is to compare it with an oximeter.

An oximeter is a medical device worn on the finger, with the help of which you can measure the accuracy of your smartwatch.

Apart from this, if you or your relatives have a premium smartwatch, you can also compare it and measure its accuracy.

Should You Rely on Smartwatch for Spo2 Monitoring?

So far, you don’t see such precise sensors in smartwatches that you rely on them.

In some smartwatches, you get the accurate Spo2, but this is not always the case; their data changes frequently, making them difficult to rely on.

Although with increasing technology, you may get to see accurate sensors in smartwatches, for now, you shouldn’t rely on any smartwatch for Spo2.

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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.