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Oxygen saturation (finger probe)

Measurements · also printed as SpO2, Oxygen saturation, O2 sat, Sats, O2 saturation

Typical UK adult range95 to 100 %

95 to 100 percent is typical; people with long-term lung disease often have a lower target band set by their team.

What this test measures

SpO2 from a finger probe estimates the share of haemoglobin carrying oxygen, using light through the fingertip.

Why doctors request it

Recorded at most clinical contacts and at home during chest infections.

What commonly pushes it up

Supplemental oxygen

What commonly pushes it down

Lung disease and chest infections
Heart conditions
Being at altitude
Cold hands, nail varnish, movement or a poor signal

Everyday reasons for a value outside the range

Cold fingers and nail varnish read low
Darker skin can read slightly high, which matters at low values
Long-term lung disease has its own lower target band

About the sample

Warm hand, still, no nail varnish.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.