Overview
This article made a comparison between Owlet and BabyO2 S2.
Baby oxygen monitor now is thought to be a useful bedtime helper that brings peace of mind to new parents or caretakers. The innovative baby monitor continuously tracks oxygen levels and heart rates and sends alarms when abnormalities are detected. The responsibility of knowing whether your baby is okay when the lights go out always makes parents anxious and sleep not well because they have to take up to check the baby’s breath many times. Then the baby breath monitor with alarms actually eases their worried minds since once there is amiss, parents will receive alarms and can make an instant response.
So is there any trustable baby oxygen monitor brand in the market? Now the Owlet Smart Sock 3 and Wellue BabyO2 S2 are chosen by many new moms. We are going to compare these two brands from some aspects as follows.

- Continuous body movement, pulse rate and oxygen tracking
- Real-time data on the monitor device, base station and phone APP, can monitor without phone
- Notifications from alarm base station and phone APP
- Mobile sleep reports
- Built-in memory to save recordings
- No Wi-Fi setting requirement
- Safe, soft and non-slip wraps

- Heart rate and oxygen tracking
- Real-time data on the phone
- Notifications from the base station
- Mobile sleep circle analysis
- Wifi requirement
- No backup memory
- Wearable socks
#1 What’s in the Box

- Wellue BabyO2™ S2 baby oxygen monitor foot: main device + Wraps + oximetry sensor cable
- Base station
- Stitched soft wraps in different sizes (0-3 years old)
- Split wraps in different sizes (0-3 years old)
- Pulse oximetry sensor cable
- Personalized sticker
- User guide in 5 languages
- Charging base station for the base station
- Type-C charging cable for the station
- Data/Charging cable for BabyO2 S2 main device
- Quick guide for split wraps
- 1-year warranty



- 3 Owlet socks (sizes 0–18 mos.)
- Sensor
- Base station
- Charging cords
- Setup instructions
- Quick reference guide
- Warranty


#2 Pricing and Guarantees
Common pros:
- One-time purchase
- No contracts; no monthly subscription or long-term contract
- Peace of Mind guarantee
Differences:
BabyO2 S2
- Economical
- 30-Day money-back guarantee
- 1-year warranty
Owlet Smart Sock 3
- Expensive price tag
- 45-Day peace of mind guarantee
- 1-year warranty
#3 Tech and Equipment
BabyO2 S2 | Owlet Smart Sock 3 | |
Bluetooth Connection | Bluetooth connection between the monitor device, base station, APP | Wi-Fi connection between the sock and APP, Bluetooth connection between the sock and the base station |
Be monitored in 2 different houses | A Bluetooth range of up to 10 feet | A Bluetooth range of up to 100 feet |
Battery life | 16 hours for the monitor device, 7 days for the base station | 16 hours for the sock |
Backup memory/ Built-in memory | Yes, the monitor main device can save recordings automatically (4 sessions, up to 10 hours for each) and can be synchronized to an APP after being connected with the phone. | No, only use the phone to record data |
- The medical-grade accurate oximetry sensor
- Real-time data on the 3 screens: main device, base station, phone APP dashboard
- Review the history data and oximetry analysis on the APP dashboard
- Receive alarms from the base station & APP
- Monitor and base station can be used independently without the phone
Owlet Pros:
- See real-time data and sleep report only on the phone
- Receive alarms from the base station
Owlet Cons:
- No backup memory
- No monitor screen
- Must use the phone to see real-time data and save history recordings
- Must be used in the Wi-Fi environment
The BabyO2 S2 is more friendly to travel. Its base station is light in weight and small in size, so easy to carry. With long battery life, you do not have to worry about its charging problem. Otherwise, its built-in memory supports saving recordings without a phone, so it won’t interfere with your daily phone use. But if you want to get the oximetry analysis for your little one, you have to connect the main device with your phone and then you can review the history data and analysis.
#4 Features and usability
BabyO2 S2 | Owlet Smart Sock 3 | |
Notifications/Reminders from the base station | Oxygen reminder, pulse rate reminder, no value reminder, moving reminder, the offline reminder | Live heart rate, oxygen level, wellness notifications, and room temperature sensors |
Adjustable audio alarms | Yes, you can customize the reminder: oxygen levels threshold, pulse rate threshold, reminder delay time | No, the Owlet Smart Sock’s preset levels cannot be changed. |
Monitor screen: Real-time readings | 3 screens: monitor device, base station, APP | Only APP |
Sleep history report | Review on APP and PC software | Review on APP |
BabyO2 S2 pros:
- Real-time monitor screen
- Adjustable parameters’ thresholds and audio alarms
BabyO2 S2 cons:
- No temperature sensor
Owlet Smart Sock pros:
- Have room temperature sensor
Owlet Smart Sock cons:
- No monitor screen
- Absolute preset oxygen norms
#5 APP Comparisons
- Free to use
- Detail sleep reports knowing your baby’s average oxygen and the time of lower than 90%
BabyO2 S2 cons:
- Don’t support multiple users
- Once you leave the dashboard, you cannot receive alarms from your phone if you don’t use the base station.




- No monthly fee is required to access the Owlet app.
- The same Owlet app account can be logged into on multiple devices.
Owlet Smart Sock cons:
- Must connect Wi-Fi
- Phone notifications are dependent on your device’s sound settings. If you have the sound off on your phone, you will not get sound notifications from the Owlet app, only vibrations.

Summary
After comparing the BabyO2 S2 baby oxygen monitor and Owlet Smart Sock3 as above, you can find the BabyO2 S2 is more economical than Owlet. Both the baby monitors are used to track your loved little one’s vital signs of oxygen levels and pulse rates and to send audible notifications to parents so as to tell them when babies need attention. The BabyO2 S2 is more convenient to carry outside and to read real-time data because of its Bluetooth connection, built-in memory and long battery life, while the Owlet doesn’t have a monitor screen and relies on your phone use too much. But on the other hand, the APP of BabyO2 S2 is not better than Owlet APP. However, it won’t affect its main purpose to review historical data and oximetry analysis. Thus, by and large, BabyO2 S2 is more cost-effective than Owlet Smart Sock.
Personal Healthcare Expert. MS in Sleep Apnea & Chronic Obstructive Pulmonary Disease, Johns Hopkins University.