Mac Terminal

In the Terminal, just type control+c to break out of the command expecting you to complete its syntax. Don't type control+z as that just throws the session in the background.

For Intel platforms only (notice the spacing around the pipe symbol).

sudo powermetrics -n 1 --samplers smc | grep "(CPU|GPU) die"

This was from a just booted Core i7 iMac:



The GPU temperature is only be available if you have a Mac with a discrete GPU. The majority of Mac configurations rely on the Intel GPU integrated into the CPU. You can see exactly what items are available by running the "powermetrics" command without filtering it through "grep":

sudo  powermetrics  -n1  --samplers  smc

Not sure this will work

Command z

Can't explain why either. On my 2014 Air running Catalina 10.15.7, the SMC sampler does not see the integrated GPU, but does return the CPU die temperature with the same command syntax as I used previously. When you use the parenthesis, it forces to be a subprocess and it does not echo results to the Terminal.

It doesn't work on my MBPro 13" mid-2012 non-Retina model either. In fact I cannot read any temps using powermetrics even when using the "all" option. I did get an error "unable to get smc values", but not sure why. Seems maybe not all Macs have this support. I am running macOS 10.15.x.

The OP may just have to resort to using MacsFanControl.

FYI, I managed to try this command on several different models of Apple laptops with varying results. It seems many laptops don't access to the temps or SMC attributes. The laptops I've been able to retrieve the SMC values have been the USB-C 2016+ models. On some older laptops it is telling me it cannot retrieve SMC values because "SMC is currently in monitor mode". I'm not sure what is going on with that error message. If you use this part of the command without adding the "grep" filter, then you will see the information provided and any error messages:

sudo  powermetrics  -n1  --samplers  smc

The command provided by @VikingOSX is incorrect as it cannot parse the "(CPU|GPU)" portion of the filter. The following updated command will work if the SMC values are accessible (notice the inclusion of the "-E" option necessary for the "(CPU|GPU)" portion of the filter to work -- tested on Big Sur):

sudo  powermetrics  -n1  --samplers  smc  |   grep  -iE  "(CPU|GPU) die"



Of course this all assumes you are using an Intel Mac since M1/M2 Macs with Apple Silicon do not have an SMC so these command will not work at all. I have no idea how to access any sensor information on Apple Silicon Macs or possible alternate methods on the Intel Macs. I normally just rely on third party apps like MacsFanControl to provide the functionality, although I may be looking into an app which can produce a sensor log over time (I don't usually need this functionality, but there are times it may prove useful).

HWTech wrote:

The command provided by @VikingOSX is incorrect as it cannot parse the "(CPU|GPU)" portion of the filter.

It was correct on my particular 2020 Intel Core i7 hardware as the screen capture was the command and its results without using the extended (-E) grep. But as you have observed, powermetrics does behave differently across varying Mac hardware, so one might have to use egrep where appropriate.

VikingOSX wrote:

HWTech wrote:

The command provided by @VikingOSX is incorrect as it cannot parse the "(CPU|GPU)" portion of the filter.

It was correct on my particular 2020 Intel Core i7 hardware as the screen capture was the command and its results without using the extended (-E) grep.

Just curious what version of macOS you are using? I was using multiple versions of Big Sur from early 11.6.1 to latest 11.6.8 on at least two different laptop models 2014 & 2017.

HWTech wrote:

On some older laptops it is telling me it cannot retrieve SMC values because "SMC is currently in monitor mode".

Seems a reboot fixed this issue. Now I have to wonder if this is related to the issue a user reported for the laptop running hot. I really miss the days when Macs acted normal and didn't have so many quirks. Hard to tell what is normal and abnormal these days.

If you want to monitor the temperature non-stop, then remove the " -n1" part of the command as that limits it to one time reporting. To terminate the command you will need to press Control + C within that Terminal window running the process.

FYI, I was hoping to test this command on a Mac running Monterey to compare my results with Big Sur and @VikingOSX. I'll see if I can remember next week. Unfortunately Apple has been making changes to the hardware and even these utilities so things don't always work as expected across various hardware and OS revisions. Somehow third party apps are able to access the temperature sensors, but I'm not sure how they do it. I'm not sure if there is anyway to do so using standard macOS command line utilities.

Personally I normally just use MacsFanControl (posted link in earlier post) to monitor the fan speed and temps since it just works. I have rarely needed to worry about logging the results. It is possible to run MacsFanControl without installing the driver as long as you don't authenticate when running the app, but it is a bit non-intuitive to do so as you must also "Cancel" one of the options. I normally just run it directly from the Downloads folder. Plus this option may prevent being able to automatically update the app. Unfortunately you cannot log the results with this method.