Blood Oxygen Monitors (Pulse Oximeters)

Zacurate Pro Series 500DL Blood Oxygen Saturation Monitor

Blood oxygen monitors, often referred to as pulse oximeters, are medical devices designed to measure the saturation of oxygen in a person’s blood. This non-invasive tool works by passing light through a translucent part of the patient’s body, usually the fingertip or earlobe, to measure the amount of oxygen in the blood. The device then provides a numerical reading which represents the percentage of hemoglobin in the arterial blood that is oxygen-saturated.

Understanding the level of oxygen saturation in the blood is crucial because it provides insights into how effectively a person’s lungs are transferring oxygen into the blood and how efficiently the circulatory system is delivering this oxygenated blood to the rest of the body. In healthy individuals, blood oxygen levels typically fall between 95% to 100%, though this range can vary slightly depending on the source. Levels below 90% are generally considered low and might indicate a medical emergency.

The top 8 Blood Oxygen Monitors

Product name Image Rating Pros Cons Best Price More information


Zacurate Blood Oxygen Saturation Monitor

Zacurate Pro Series 500DL Blood Oxygen Saturation Monitor
5 star review
  • Accurate readings
  • Durable construction
  • Suitable for all ages
  • Can be slow to get a reading
  • Not as feature-rich as some models
  • May not fit larger fingers comfortably
Coming Soon!


CONTEC LED CMS50M Pulse Oximeter

CONTEC LED CMS50M Pulse Oximeter
  • Super affordable
  • Straightforward to use
  • Decent battery life
  • No advanced features like alarms
  • Some find display orientation inconvenient
  • Potential accuracy issues for some users
Coming Soon!

Innovo Deluxe iP900AP Fingertip Pulse Oximeter

Innovo Deluxe iP900AP Fingertip Blood Monitor
  • Features both Plethysmograph and Perfusion Index
  • Reliable accuracy
  • Adjustable display brightness
  • Pricier than some models
  • Larger design might be less portable
  • Batteries can drain quickly
Coming Soon!

mibest OLED Finger Pulse Oximeter

mibest OLED Finger Pulse Oximeter
  • Bright OLED display
  • Affordable
  • Comes in various colors
  • Some durability concerns
  • May struggle with cold fingers
  • Strap quality can be inconsistent
Coming Soon!

Wellue O2Ring Oxygen Tracker

Wellue O2Ring Oxygen Monitor
  • Wearable design for continuous monitoring
  • Vibrational alerts for low oxygen.
  • Rechargeable
  • Comes with an app that can be downloaded on your phone to track your blood levels
  • Expensive
  • Might not fit all finger sizes comfortably
  • Requires a learning curve for some users
Coming Soon!

Santamedical Generation 2 Fingertip Pulse Oximeter

Santamedical Generation 2 Fingertip Pulse Oximeter
  • Compact design
  • Quick readings
  • Has been on the market for a long time (trusted)
  • No advanced features
  • Screen can be dim in bright light
  • Some concerns about long-term durability
Coming Soon!

LAccuMed Blood Oxygen Monitor

AccuMed CMS-50D1 Fingertip  Blood Oxygen Monitor
  • Affordable
  • Comes with a carrying case
  • Easy-to-read LED display
  • Basic feature set
  • Some report inconsistencies in readings
  • Not as robust as other models
Coming Soon!

FaceLake FL400 Pulse Oximeter

FaceLake FL400 Pulse Oximeter
  • Comes with accessories like a case and lanyard
  • Good value for money
  • Easy to use
  • Some have reported delays in getting readings
  • May not fit very small or large fingers comfortably
  • Occasional quality control issues
Coming Soon!

Additional Reading

Pulse oximeters have a variety of applications in clinical and home settings. In hospitals, they are frequently used in intensive care units, surgical centers, and during anesthesia procedures to monitor a patient’s oxygen levels continuously. They help medical professionals detect conditions like hypoxemia (low blood oxygen) promptly, allowing for immediate intervention. These devices are also invaluable in managing patients with respiratory diseases, such as chronic obstructive pulmonary disease (COPD), asthma, and pneumonia, among others.

During the COVID-19 pandemic, the importance of blood oxygen monitors was underscored, as they played a pivotal role in monitoring and managing patients infected with the virus. Given that one of the severe complications of COVID-19 is its impact on lung function, many patients and healthcare professionals relied on pulse oximeters to detect early signs of declining oxygen levels, even before the onset of other symptoms.

The History of Blood oxygen monitors

The history of blood oxygen monitors, also known as pulse oximeters, ties medical innovation and technological advancement. It all began in the late 19th and early 20th centuries, when scientists first started to understand the importance of oxygen in the blood and the need for its measurement.

Initial attempts at measuring blood oxygen levels were invasive, requiring blood samples to be taken and analyzed. This changed dramatically with the work of Glenn Allan Millikan in the 1940s. Robert Andrews Millikan – an American experimental physicist, developed the first oximeter, which was still somewhat cumbersome and primarily used for research rather than routine clinical monitoring.

The real breakthrough came in the 1970s with the development of the pulse oximeter by Aoyagi Takuo, a Japanese bioengineer. His innovation was revolutionary because it was non-invasive, using a sensor placed on a thin part of the patient’s body, usually a fingertip or earlobe, to measure blood oxygen levels. The device worked by emitting light through the skin and measuring the light absorption by oxygenated and deoxygenated hemoglobin in the blood, giving a reliable estimate of blood oxygen saturation.

This new technology rapidly gained popularity in the medical community for its ease of use, speed, and non-invasiveness. By the 1980s, pulse oximeters had become compact and user-friendly, making them a staple in operating rooms and critical care settings. Their importance was further highlighted by the inclusion of pulse oximetry in standard monitoring guidelines for anesthesia, revolutionizing patient safety during surgery.

Over the years, technological advancements have made pulse oximeters increasingly accurate and reliable. Modern pulse oximeters are small, portable devices that provide real-time, continuous monitoring of blood oxygen saturation levels. They have become essential tools not just in hospitals but also in outpatient settings and home care, particularly for patients with respiratory or cardiac issues.

The COVID-19 pandemic underscored the value of pulse oximeters for monitoring oxygen levels in patients with respiratory infections. The widespread use of these devices during the pandemic highlighted their role in remote patient monitoring and management of respiratory illnesses.

Today, blood oxygen monitors are an integral part of healthcare, used in a wide range of medical settings and situations. Their development from a cumbersome, invasive procedure to a compact, non-invasive, and widely accessible technology is a testament to the progress in medical instrumentation and patient care.

Components of Blood oxygen monitors

Blood oxygen monitors, commonly known as pulse oximeters, consist of several key components that work together to measure the oxygen saturation level in the blood. Here are the main components:

Probe/Sensor – The most visible part of a pulse oximeter is the probe or sensor. This is the part that attaches to the body, usually to a fingertip or earlobe. The probe houses light-emitting diodes (LEDs) and a light detector.

Light-Emitting Diodes (LEDs) – The LEDs in the probe emit light at two different wavelengths – one in the red visible light spectrum and the other in the infrared spectrum. These lights pass through the skin and are absorbed by the blood.

Photodetector – Opposite the LEDs in the probe is the photodetector, which measures the amount of light that passes through the finger or earlobe. It detects the changes in light absorption of oxygenated and deoxygenated blood.

Microprocessor – The microprocessor is the brain of the pulse oximeter. It processes the signals from the photodetector to calculate the oxygen saturation level. It takes into account the varying absorption rates of oxygenated and deoxygenated hemoglobin for the emitted light.

Display Screen – This component displays the results, showing the oxygen saturation level (SpO2) and often the heart rate. Advanced models may show additional information like pulse waveforms.

Power Source – Pulse oximeters are typically powered by batteries, which can be either replaceable or rechargeable. This makes the device portable and convenient for use in various settings.

Casing – The outer casing of the pulse oximeter protects the internal components and is usually made of durable plastic. It is designed for ease of use and to withstand regular handling.

Controls/Interface – Some models include buttons or a touchscreen interface to control the device, such as turning it on/off, adjusting settings, or switching between display modes.

Who should use Blood oxygen monitors

Blood oxygen monitors, or pulse oximeters, are useful for a variety of individuals in different scenarios:

Patients with Respiratory Conditions – Individuals suffering from chronic respiratory conditions like COPD (Chronic Obstructive Pulmonary Disease), asthma, or pneumonia can benefit from using a pulse oximeter to monitor their oxygen levels, ensuring they stay within a safe range.

Patients with Cardiac Conditions – Those with heart conditions, such as congestive heart failure, can use pulse oximeters to monitor their oxygen saturation, as these conditions can affect oxygen levels in the blood.

People with Sleep Apnea – Pulse oximeters can be used overnight to monitor oxygen levels in individuals with sleep apnea, a condition where breathing repeatedly stops and starts during sleep.

Athletes and Fitness Enthusiasts – Athletes, especially those training at high altitudes, use pulse oximeters to monitor their oxygen saturation levels to ensure they are getting enough oxygen during intense physical activity.

Individuals Recovering from COVID-19 – During the COVID-19 pandemic, pulse oximeters have been used by patients recovering at home to monitor their oxygen levels, as COVID-19 can significantly affect lung function.

Pilots and Mountaineers – People exposed to high altitude environments, like pilots and mountaineers, use pulse oximeters to monitor their oxygen saturation levels, as oxygen levels can decrease at high altitudes.

Postoperative Patients – After certain surgeries, particularly those involving the heart and lungs, pulse oximeters are used to continuously monitor patients’ oxygen levels.

What Blood oxygen monitors are NOT intended for

While blood oxygen monitors are valuable tools for many individuals, there are specific situations and individuals for whom these devices may not be suitable or whose readings might not be reliable:

Individuals with Certain Skin Conditions – People with certain skin conditions or very thick skin, especially at the site where the pulse oximeter is placed (like the fingertip), may get inaccurate readings.

Those with Severe Blood Flow Issues – In cases of severe peripheral vascular diseases where blood flow to extremities is greatly reduced, pulse oximeters might not provide accurate readings.

Patients with Nail Polish or Artificial Nails – The presence of nail polish or artificial nails can interfere with the pulse oximeter’s light sensor, leading to inaccurate readings.

People Relying Solely on Oximeters for Respiratory Health – Individuals should not use pulse oximeters as the sole indicator of their respiratory health, especially in the context of serious conditions like COVID-19, as normal oxygen readings can give a false sense of security.

Individuals with Unstable Hemoglobin Levels – Conditions that affect hemoglobin levels, like anemia, might also affect the accuracy of pulse oximeter readings.

People with Darker Skin Pigmentation – Some studies suggest that pulse oximeters might be less accurate in individuals with darker skin pigmentation, though more research is needed in this area.

Individuals Seeking Medical Diagnosis –Pulse oximeters should not be used as a tool for self-diagnosis; they are meant for monitoring and should be used in conjunction with professional medical advice.

Pros and Cons table of Blood oxygen monitors


  • Pulse oximeters provide a painless and non-invasive method to measure blood oxygen levels, which is less stressful for patients compared to blood tests.
  • These devices offer immediate results, are easy to operate, and don’t require specialized training for basic monitoring.
  • Most pulse oximeters are small, lightweight, and portable, allowing for monitoring on the go or at home.
  • They are essential in managing and monitoring respiratory and cardiac conditions, including COPD, asthma, and heart failure.
  • Pulse oximeters provide rapid assessment of oxygen levels in emergency settings, aiding in timely decision-making.
  • Beneficial for athletes and those in high-altitude environments to monitor oxygen levels during strenuous activities.
  • Can be used overnight to monitor oxygen levels in individuals with conditions like sleep apnea.


  • Factors like poor circulation, skin pigmentation, nail polish, and movement can affect accuracy.
  • Should not be solely relied upon for diagnosing conditions; professional medical evaluation is necessary.
  • Provides only blood oxygen saturation and pulse rate, not a comprehensive view of respiratory or cardiac health.
  • While many are affordable, more advanced models can be expensive.
  • Users may over-rely on these devices, potentially overlooking other critical symptoms or delaying seeking medical advice.
  • Misinterpretation of readings can occur if users are not properly educated about what the numbers mean.
  • Being electronic devices, their functionality is contingent on having a sufficient power source.

Studies regarding the benefits of Blood oxygen monitors

    1. Title: Cardiorespiratory and Pulse Oximetry Monitoring in Hospitalized Children
      • Summary: This study explores the use of pulse oximetry in hospitalized children, focusing on its role in monitoring cardiorespiratory health.
    2. Title: Smart wearable devices in cardiovascular care: where we are and how to move forward
      • Summary: The study reviews the accuracy and application of wearable devices, including blood oxygen monitors, in cardiovascular care, emphasizing their potential in improving patient outcomes.
    3. Title: Study of an Oxygen Supply and Oxygen Saturation Monitoring System for Radiation Therapy Associated with the Active Breathing Coordinator
      • Summary: This research discusses an oxygen supply and monitoring system used in radiation therapy, highlighting the benefits of using pulse oximetry to ensure patient safety during treatment.
    4. Title: A Review of Monitoring Methods for Cerebral Blood Oxygen Saturation
      • Summary: This review delves into various methods for monitoring cerebral blood oxygen saturation, including pulse oximetry, providing insights into their effectiveness in different clinical scenarios.
    5. Title: Brain Tissue Oxygen Monitoring and the Intersection of Brain and Lung
      • Summary: The study examines different technologies for measuring oxygen in the brain, discussing their applications and limitations in medical settings.