Why would you?
If your MacBook, Mac Pro, Mac mini, or iMac gets put under a lot of stress whether it be gaming, video editing, producing renderings, or simply processing a lot of data which is taxing on the CPU then it might be a good idea to monitor your CPU temperature. Every CPU has a maximum operating temperature established by the manufacturer and is a CPU exceeds that threshold limit then it is possible that you may cause severe damage to your CPU and quite possibly damage other components. I explain my temperature monitoring strategy on my Mac mini here.
How do I check my CPU temperature?
There are several ways to do this via apps. I’m not going to do an in-depth review of each option’s features and cost since they constantly change and it’s best you check them out individually to see if they satisfy your needs as everyone’s needs are different. My personal favorite is Hardware Monitor because of its simplicity and the fact that I can display the CPU temperature right on my menu bar which gives me that instant feedback. Helpful instructions on osxdaily.com article. Another app is iStat Menus which provides more system info than just temperatures. Monit is a great app with a beautiful UI and accessible from the Notification Center. Fanny also has a great UI and monitors your fan speeds – also accessible from the Notification Center.
If you’re after simplicity, Hardware Monitor is awesome. If you’re Batman and want the most stats you can get, then go with iStat Menus. If you’re more of a visual person and like having temps and other info displayed in the Notification Center then go with either Monit or Fanny. Fanny if you’re concerned about fan speeds too.