What are the differences between the Smart Sock 2 and 3?

We heard from many parents after the launch of the Smart Sock 3 who had used a Smart Sock 2 and wanted to know how the Smart Sock 3 is different. 


Here’s a summary of the differences:


New design 

  • We completely redesigned all components of the Smart Sock 3—the Sock, Sensor and Base Station. The Sock and Sensor go on the foot in an entirely new way. Sock fit is very important to ensuring you don’t get unnecessary notifications or red marks. Take a look at our placement instructions to ensure you’re using the Sock correctly.
    • Pro tip: the owl on the Sensor should always be on the outside of the pinky toe, never the big toe.
  • Smart Sock 3 has 2 sizes, size 1 (up to 12 lbs) and size 2 (12-30 lbs). There are right and left versions in each size, so you have a total of four fabric socks.
  • The new design includes wireless charging so there are no cords to plug in after a sleep session—just drop the Sock on the Base Station and walk away!
  • The new design of the Sensor and Sock allowed us to make improvements to accuracy, specifically for oxygen readings. These are marginal improvements but could result in slightly different readings than what you might have seen in your sessions with the Smart Sock 2. Know that we are constantly working to improve our algorithms and accuracy for live readings and history.
  • We have added ambient light sensing to the Smart Sock 3 Base Station so you no longer have to manually adjust light levels from day to night. 
  • The Base Station now only has one button, used for everything from registration, turning on and off monitoring, pausing notifications, and turning off the sock. 


Monitors through gentle motion

  • The Smart Sock 2 does not track through motion, therefore we suspend readings and notifications when motion happens during a session. This means if you left your Smart Sock 2 on during activity such as diaper changes, burping or nose cleanouts and your little one got upset (causing heart rate or oxygen levels to leave preset zones) we wouldn’t send a notification. With the Smart Sock 3 we may still get readings during these events and you could get a red notification if your child gets upset. 
  • Monitoring through motion may also mean you are able to get readings while your little one is awake.
    • Please note: the Smart Sock is intended for use during sleep, and it’s important to note various normal activities such as feeding while awake can cause notifications that you would not see with a Smart Sock 2 because of motion limitations. 



  • When you take the Sock off the Base Station you have 2 minutes to get the Sock placed on your baby’s foot to get a reading before a yellow notification will sound. When the Sock comes off the foot after getting readings a yellow notification will sound in 60 seconds. To avoid yellow notifications at the end of a session simply turn off your Base Station before removing the Sock. 
  • The Smart Sock 3 allows you to pause a notification sound on the Base Station with a short press or in the Owlet app rather than turning off the Base Station during a notification event. The sound will pause on the Base and in the app for 60 seconds, or until the situation has been remedied if sooner than 60 seconds. 


App differences

  • The Smart Sock 3 shows battery levels in hours and minutes while in use, and displays percent charged while charging. 
  • With the Smart Sock 2, you can adjust yellow and blue notifications in the app to delay the default threshold for time to notify or to mute sound entirely. The Smart Sock 3 does not have this capability because of its better fit and ability to track through gentle motion.