Best Pulse Oximeter of all-night logging

anyone know the best pulse oximeter of all-night logging?

i would like to optimize the following:

  • comfort – to wear during sleep, say on finger or wrist, etc.
  • ample logging memory – every few seconds for an entire night
  • economy – not ridiculously overpriced for, e.g. hospital budgets

minor hacking fine if path previously trodden. for instance, if the above don’t exist in one device, then if someone has combined a cheap non-logging oximeter with a cheap general-purpose data logger, then cool! sounds like fun :slight_smile:


I wrote a guide on buying a pulse oximeter in June 2011. Most of them are wildly inaccurate if you’re moving, with the honest manufacturers stating that the device “will NOT monitor SPO2 during activity and movement. You must stop the current activity and take the reading while stationary. Movement will cause readings to be affected by artifact”. Others are not designed to be used for over 2 hours at a time.

The best one was the SPO Medical PulseOx 7500™ (which Amazon discontinued in the meantime). It’s still the latest one developed by SPO Medical as of Dec 2012, even though it was launched before May 2006.

I bought it and was completely unimpressed with its consistency. I have some photos somewhere of situations that don’t make sense, to the tune of holding my breath for a minute and my oxygen level increasing. I could dig them up if someone is really interested, but the bottom line was that I returned the oximeter.

I came accross a very interesting website with more info on this product:

I use the CMS50e which is quite satisfactory for occasional overnight use. It is not a sport oximeter. Cost me around $100 a few years ago. Most people who belong to the this forum: use the CMS50e or CMS50f
See this thread in the forum for a running dialogue about the CMS50: Search the sleep apnea forum for more.
See these sites for more info on overnight recording pulse-ox’s:


This is a great device! I found some more information on this website:

I love this device. I’m a mountain climber by profession and use to go on various treks. SantaMedical Fingertip pulse oximeter was gifted to me by my friend. It’s a portable device which can be carried along. And to check my pulse rate, I just need to insert my finger in the given socket and within few seconds my pulse rate and oxygen saturation level are displayed in red numerals in the monitor display placed on the device itself.

Santamedical SM-110 Pulse Oximeter included Storage device for history recording of Pulse rate. this Device 24 hours continuous monitor pulse rate and SpO2 without break.

I have a CMS-50F that I purchased about 5 years ago for about $120 to use for overnight logging. Seemed to work well but the problem was that the measurements in the log file (csv format) don’t have time stamps. There is a time stamp auto generated for the file name but I seemed to use the datetime the data was downloaded, not the time it started or finished logging. So there was no way to determine an accurate time for the measurements. It does provide a binary log file in “.spor” format that I assume has the accurate time info but you have to use there software to open it. Sample output log files attached.

There are newer versions that may work better.

_201201052017.spoR (64.3 KB)
_201201052017.csv (349.7 KB)

You can give this method a try:

Try a search for spO2.exe