Quick Answer
A pulse oximeter usually shows two readings: SpO₂, which estimates the percentage of oxygen carried in your blood, and pulse rate, which shows heartbeats per minute. Read both after the display settles, and ask a healthcare provider to interpret results for your health situation.
A fingertip pulse oximeter shows SpO₂ as a percentage and pulse rate in beats per minute, often marked “PR” or “bpm.” These are estimates, not diagnoses, and should be interpreted with your symptoms, care plan, and device instructions. Health Canada explains that pulse oximeters use light to check pulse rate and estimate how much oxygen the blood is carrying.
What Is SpO₂ on a Pulse Oximeter?
SpO₂ is the pulse oximeter’s estimate of blood oxygen saturation. It represents the percentage of haemoglobin carrying oxygen and is displayed with a percent sign.
A pulse oximeter does not collect a blood sample. It estimates oxygen saturation by passing light through the fingertip and analysing how the light is absorbed, as described in Health Canada’s pulse oximeter overview.
The reading may be labelled SpO₂, oxygen saturation, or O₂ saturation. It does not explain why a value changed; a healthcare provider should interpret personal targets.
What Is Pulse Rate on a Pulse Oximeter?
Pulse rate is the number of pulse beats detected in one minute. It usually appears as “PR,” “pulse,” or “bpm.”
The device calculates pulse rate from the same optical signal used for the oxygen estimate. It can change with movement, activity, stress, temperature, and positioning, so it should not be treated as a diagnosis.
What Are the 2 Readings on a Pulse Oximeter?
The two main readings are SpO₂ and pulse rate. SpO₂ estimates oxygen saturation as a percentage; pulse rate shows detected beats per minute.
Read Your Display in 10 Seconds
- Find the number followed by % or labelled SpO₂.
- Find the number labelled PR, pulse, or bpm.
- Check whether the pulse bar or waveform looks steady.
- Keep your hand still until the numbers stop changing quickly.
- Record both values only when your care plan asks you to do so.
How Do You Read a Pulse Oximeter Display?
Identify the labels, then wait for the screen to settle. Layouts vary by model, so the user manual is the best guide to symbols and display orientation.
Some devices also show a PI or perfusion index, a pulse bar or waveform, and a battery icon. Check the manual because layouts and symbols vary.
If your device shows PI, do not apply a generic “pulse oximeter PI normal range by age” to yourself. PI displays vary, and health conclusions should come from a healthcare provider.
What Does a Pulse Oximeter Readings Chart Show?
A pulse oximeter readings chart can explain the display without assigning a universal medical target.
| Reading | What it typically shows | Notes |
|---|---|---|
| SpO₂ | A percentage estimate of blood oxygen saturation | Personal interpretation should come from a healthcare provider |
| Pulse rate or PR | Detected pulse beats per minute, shown as bpm | May change with activity, movement, temperature, or stress |
| PI, if supported | A device-specific indication of pulse-signal strength | Not every model displays PI; check the manual |
| Pulse bar or waveform | A visual representation of the pulse signal | An unstable pattern may suggest movement or weak signal quality |
This is a display guide, not a pulse oximeter normal range chart.
How Does a Pulse Oximeter Work?
A pulse oximeter uses light to estimate oxygen saturation and detect pulse rate. The fingertip clip contains a light source and sensor on opposite sides of the finger.
The device analyses changes in light absorption and the pulsing signal to calculate the display. Because this is an estimate, correct placement and a stable signal matter. Health Canada’s guidance for healthcare providers explains that pulse oximeter measurements are estimates and may differ from actual blood oxygenation measured through arterial blood gas testing.
How Do You Use a Pulse Oximeter Correctly?
Follow the manufacturer’s instructions, warm your hands, position the finger correctly, and remain still.
- Sit quietly and support your hand.
- Make sure the hand is warm, clean, and dry.
- Remove interfering nail products when practical.
- Insert a suitable finger fully into the device.
- Press the power button as directed.
- Stay still until the display settles.
- Record the reading only when required by your care plan.
The ZenCare Fingertip Pulse Oximeter displays SpO₂ and heart rate. Follow its user instructions rather than directions written for another model.
Which Finger Should You Use for a Pulse Oximeter?
Use a finger that fits the sensor comfortably and follow the manufacturer’s instructions. There is no single finger that is universally best for every device and person.
Make sure the finger is inserted fully, the hand is warm and supported, and the screen has time to settle. Try another suitable finger if the signal remains unstable.
What Can Affect Pulse Oximeter Accuracy?
Accuracy can be affected by device use, finger condition, the environment, and individual physical factors.
| Factor | How it may affect the reading | Practical response |
|---|---|---|
| Cold hands | May weaken the fingertip pulse signal | Warm the hands gently |
| Movement or tremor | Can interrupt the optical signal | Support the hand and remain still |
| Nail polish or artificial nails | May interfere with light passing through the finger | Use a suitable bare nail when possible |
| Incorrect placement | Can misalign the sensor | Reinsert the finger according to the manual |
| Bright light | May interfere with optical sensing | Move indoors or shade the device |
| Moisture or sanitiser | May affect sensor contact | Make sure the hand and device are dry |
| Weak fingertip circulation | May produce an unstable signal | Warm and reposition the hand |
| Poor finger-to-sensor fit | Can reduce signal quality | Use a suitable finger without forcing the clip |
| Darker skin pigmentation | Some readings may be less accurate | Do not rely on the number alone |
Health Canada’s consumer guidance identifies incorrect sensor placement, movement, nail products, finger size, excessive light, moisture, cold, and certain physical or medical factors as possible influences on accuracy. The same official guidance notes that published reports have found pulse oximeter readings may be less accurate in people with darker skin.
What Is a Normal SpO₂ or Pulse Rate?
There is no single number that applies to every reader. Expected values may differ with altitude, health conditions, medicines, activity, and care plans.
Ask your doctor what SpO₂ and pulse-rate values are expected for you, how to record them, and when a change requires action. Do not use a generic pulse oximeter readings chart as a substitute for personal guidance.
When Should You Contact a Healthcare Provider About a Reading?
Contact a healthcare provider when readings are repeatedly outside the personal range given to you, keep declining, do not match your symptoms, or remain unstable after correcting obvious testing issues.
Do not rely only on the oximeter if you have chest pain, difficulty breathing, shortness of breath, a fast pulse, or blue, white, or grey lips, gums, face, or nails. Health Canada recommends considering symptoms alongside pulse oximeter readings rather than relying on the display alone. Seek urgent care or call 911 for severe, sudden, or worsening symptoms.
For product setup, order, or technical questions—not medical interpretation—contact our support team.
Why Does Health Canada Licensing Matter?
ZenCare’s website states that its products are licensed by Health Canada for sale in Canada. Licensing is an important regulatory trust signal, but it does not mean every individual reading will be exact or replace correct device use and professional interpretation.
Explore ZenCare’s Health Canada licensed health monitoring devices or learn more About ZenCare.
Frequently Asked Questions
For more product information, visit our FAQ page.
What Are the 2 Readings on a Pulse Oximeter?
The two main readings are SpO₂ and pulse rate. SpO₂ estimates blood oxygen saturation and is shown as a percentage. Pulse rate indicates detected beats per minute and is generally labelled PR, pulse, or bpm. Some models also display PI or a waveform.
What Is a Normal SpO₂ Reading?
A personal SpO₂ target should come from a healthcare provider, not a generic chart. Expected readings vary with altitude, health history, and care plan. Ask your provider what applies to you and what action to take when it changes.
What Is a Normal Pulse Rate on a Pulse Oximeter?
There is no single pulse-rate value for every person. Pulse rate can change with activity, stress, temperature, medicines, and health conditions. A healthcare provider can explain your expected resting range and whether repeated changes need assessment.
How Do I Read a Pulse Oximeter?
Identify the number labelled SpO₂ or followed by a percent sign, then find the value labelled PR or bpm. Keep your hand supported and still until the screen settles. Check the manual if the display includes a waveform, pulse bar, PI, or rotating layout.
What Can Make a Pulse Oximeter Reading Inaccurate?
Cold hands, motion, incorrect placement, nail products, bright light, moisture, weak circulation, poor sensor fit, and some physical or medical factors can affect a reading. Correct obvious testing issues and repeat only as instructed.
Which Finger Should I Use for a Pulse Oximeter?
Use a finger that fits comfortably and follow the manufacturer’s placement instructions. Keep the hand warm and still and insert the fingertip fully. Try another suitable finger if the signal remains unstable.
Can a Pulse Oximeter Reading Tell Me If Something Is Wrong?
A single pulse oximeter reading cannot diagnose or rule out a medical condition. Consider it alongside symptoms and your care plan. Contact a healthcare provider about persistent or unusual results, and call 911 for severe breathing difficulty, chest pain, fainting, or other urgent symptoms.