The premise of the Apple Watch is simple and its aim is discrete. A simple, yet minimalistic device that encompasses all features related to fitness on your wrist. With that said though, not everything is as simple as it seems. 

If you are rather inquisitive, you must’ve noticed an aura of lights gleaming through the underside of your watch ever so often. If that’s the case, don’t worry! We’ve got a complete explanation of all the lights, blue, red, and green alongside what they mean right here!

Why Are There Lights On An Apple Watch?

Regardless of color, the lights on an Apple Watch are used to collect various sorts of information on the multitude of sensors present on your watch. Since each color has a different wavelength and frequency, they can be used to identify specific metrics of your body.

So, no matter what the color – if you see your Apple Watch emanating light from its underside, it is definitely going through some sort of measurement process. That particular process though is dependent on what particular sensor is activated and so is the color.

If you want a quick answer, here’s a table that lets you know what each of the lights mean on an Apple Watch:

ColorRed LightBlue LightGreen Light
MeaningBlood Oxygen Sensor (SpO2)Assistive TouchHeart Rate Sensor

What Does The Green Light On An Apple Watch Mean?

The green light on an Apple Watch is activated when the watch is trying to measure your heart rate. The reason why it is green is that your blood absorbs the highest amount of green light. Therefore, it leads to a more accurate calibration.

In essence, if you see a green light on your Apple Watch or any heart rate measuring tool – your heart rate sensor is being used! However, you might also see the Watch light up even when you are not using it – what is it measuring then?

Well, if your watch lights up green even if you aren’t wearing it, it means that there’s a workout in progress. On those occasions, your Watch may occasionally light up to get a reading of your heart rate. Of course, when it has no heart rate to sense, it immediately stops after a few seconds.

Check out how accurate is Apple Watch’s heart rate

Can You Turn Off Green Lights On The Apple Watch?

The only way to turn off the green light on the Apple Watch is to disable heart rate measurement altogether. Sadly, that feature inhibits your Watch to a great extent. If you are tired of erratic measurements, you can turn off the Automatic Workout feature on the Apple Watch.

Here’s how you can do so:

  • Open the Settings app on your Apple Watch
  • Head to Privacy then scroll down to Health
  • Tap on Heart Rate and disable it

You might also need to turn off High Heart Rate and Low Heart Rate Notifications in order to ensure your Watch does not measure your heart rate and therefore use the green light at all.

Note: Your Watch may still sporadically use the heart rate sensor and therefore emit a green light even after you’ve turned everything off. As of yet, there’s no real fix to this.

What Does The Red Light On The Apple Watch Mean?

If you have an Apple Watch Series 6 or Series 7, you must’ve noticed a red light emanating from the underside of your Watch too. This light is used to measure your SpO2 (commonly referred to as oxygen saturation). The red light is actually an infrared sensor that is able to accurately determine the color of your blood. The darker the color, the lower your concentration and vice versa.

You’ll often find this light shooting out alongside the green one too. This feature is used to determine both your oxygen saturation and heart rate in conjunction with each other to derive more accurate readings. 

Can You Turn Off The Red Lights On The Apple Watch?

Yes, you can! The only way to do this so far is to completely disable blood oxygen measurements on your Apple Watch. With it disabled, you won’t be able to use some of the features the watch has (low oxygen concentration level warnings.) 

Here’s how you can disable the red lights on an Apple Watch:

  • Open the Settings app on your Apple Watch
  • Head to Privacy then scroll down to Health
  • Tap on Blood Oxygen Measurements and disable it

Do note that both the Blood Oxygen and Heart Rate sensors are imperative to the overall health and fitness-related features of your Apple Watch. Therefore, disabling them might not be the best move.

Why’s There A Red Dot At The Top Of My Apple Watch?

The little red dot at the top signifies that you have unread notifications. In essence, it acts as an indicator that is displayed only when you have a new notification of any kind. This indicator is also present in Do Not Disturb mode.

Rather than cluttering the watchface with a needless amount of notifications, Apple sought out the smart route and instead incorporated a tiny little indicator that helps users identify whether they need to be on the lookout for a notification!

How To Turn off The Red Dot On Apple Watch?

Thankfully, if you don’t like a red dot bogging down your screen, turning it off is quite simple; here’s how you can do so:

  • Open the Watch application on your iPhone
  • Head to My Watch
  • Now, tap on Notification
  • There, you’ll be able to enable and disable the Notifications Indicator which is the red dot on your screen.

Why Is There A Blue Light On My Apple Watch?

Credit: The Verge


If you have a blue light emanating around the corner of your Apple Watch, you have turned on Assistive Touch. With this feature, you’ll be able to use hand gestures to navigate through your Apple Watch.

How To Turn Off Blue Lights On The Apple Watch?

Turning Assistive Touch off will pose no harm to your device and won’t inhibit your daily fitness-related activities either. Here’s how you can disable it:

  • Open the Settings application on your Apple Watch
  • Now, head to Accessibility, and scroll down to Assistive Touch
  • Tap on Assistive Touch to disable it.

If you are wondering whether you can use Assistive Touch without turning the annoying blue borders, sadly – there is no way for you to do so right now. We’re hoping Apple implements a fix soon.

Are There Orange, Purple, Yellow, Or Other Lights On An Apple Watch?

While we’re big fans of rainbows, there are no other lights on an Apple Watch except red, blue, and green. If you see some other light – there’s a chance that might just be the display leaking or some sort of color may have attached to your Watch’s sensors.

In any case, if you see any other foreign color, it is worth checking the underside of the watch out for any faults / abnormalities. 

Founder & Chief Editor | + posts

I bought my first smartwatch in 2018 and have been wearing one ever since. It might get frustrating at times to receive 100 notifications a day. That's why we need to know how to make the best of them and how to use them to improve our daily lives, not the other way around. I write about the newest smartwatches, I create top picks, and I write helpful guides and simply explain complicated things.