Core Temp
Open Hardware Monitor
SpeedFan
HWMonitor
Sidebar Diagnostics
CPU-Z
iStat Menus
Speccy
eul
Stats
iStat Menus
RunCat
Stats Panel
SpeedFan
Open Hardware Monitor
MenuMeters for El Capitan
eulCore Temp is free and easy to use CPU temperature monitoring software. Displays core temperature in easy to understandable manner. Great tool helps us to keep an eye on your CPU Temperature to avoid Hardware failure.
Open Hardware Monitor - Monitors temperature sensors, fan speeds, voltages, load and clock speeds, with optional graph.
Stats - Simple macOS system monitor in your menu bar.
SpeedFan - Hardware monitor for Windows that can access digital temperature sensors located on several 2-wire SMBus Serial Bus. Can access voltages and fan speeds and control fan speeds. Includes technical articles and docs.
iStat Menus - "An advanced Mac system monitor for your menubar."
HWMonitor - HWMonitor is a hardware monitoring program that reads PC systems main health sensors : voltages, temperatures, fans speed.
RunCat - This cat runs at the speed according to the CPU usage of your Mac. By looking at its running, you can see how much your CPU load is.