Oximeters
Nail Polish and Pulse Oximeters: Does the Color Change Your Reading?
Yes, nail polish can change the reading on a fingertip pulse oximeter, and the color matters. In the studies, the trouble came mostly from dark shades…
Home health devices
What does that number on the screen actually mean?
A plain-English guide to the devices people use at home — pulse oximeters, CPAP machines, sleep trackers and hearing aids. What the readings mean, which features are worth paying for, and when to stop reading and call your doctor.
Explore
What are you trying to work out?
Every guide on the site, grouped by the device in your hand.
Comparisons
Which one should you buy?
Two devices, side by side, compared on the things that actually differ.
Fresh
Latest guides
Newest first.
Method
How I judge a device
Home health gadgets are sold on features that sound impressive and rarely matter. These are the five things I actually check.
01
Is it accurate enough to act on?
A consumer oximeter has a margin of error. If a device cannot tell 94% from 90%, its readout is decoration.
02
Can you read it?
Screen size, contrast and whether the display rotates. It is one of the most common complaints in owner reviews, and spec sheets almost never mention it.
03
Does it fit the person using it?
Cold hands, thick fingers, nail polish, tremor. All of them change whether a fingertip device works at all.
04
What happens to your data?
Whether it needs an app, an account, or a subscription to show you your own readings.
05
When does it stop being enough?
Every guide here says plainly at what point a device is no longer the right tool and you need a clinician.