System Monitor is an application for the menu bar of macOS, designed to inform you unobtrusively about the activity of your computer. You can retrieve up-to-date technical data any time, like process load, CPU temperature, main memory consumption, storage space, disk activity, communication on network interfaces, etc. By positioning the app in the menu bar, as least screen real estate as possible will be wasted. The program monitors your system continuously and is readily available when you need it.
If desired, System Monitor can also simulate the flickering activity lights of hard drives or network sockets in the menu bar. This is possible either in color or —perfectly integrated into the design of macOS— in inconspicuous black-and-white. PC switchers who miss this feature on Macintosh computers can easily retrofit this function with System Monitor.
System Monitor allows you to monitor the following metrics of your computer:
- Load of the total system, separated in load of the operating system, user programs, and programs with reduced priority
- Load of the individual processor cores
- Load of graphics processors (for supported GPUs)
- Number of processes currently in the system
- Uptime since the last start of the system
- General thermal status of the computer hardware
- Memory use of the operating system and all running programs
- Memory usage of graphics processors (for supported GPUs)
- Number of swap-ins from disk storage into main memory
- Number of swap-outs from main memory to disk storage
- Size of the currently used swap space
- Used storage space on disk volumes currently connected to the system. The set of volumes to monitor can be customized freely.
- Current transfer rates and bandwidths for connected hard drives. The set of disks to monitor can be customized freely. Statistics include the amount of read and written data, the number of read and write events, the peak performance transferring to and from a drive, and all accumulated data since the last start of the system.
- Display of the network interfaces currently active and operating with TCP/IP
- Display of the public Internet address, even if your computer uses a router to connect to the Internet
- Automatic tracking which network interface is currently connected to the Internet
- Current transfer rates and bandwidths for active network interfaces. The set of interfaces to monitor can be customized freely. Statistics include the amount of sent and received data, the number of packets, the peak performance of data transfer, as well as all accumulated data since the last start of the system.
- Read and write activity of hard drives, and standby mode of hard drives
- Send and receive activity of network interfaces
For specific items, the history of the last 30 seconds can be visualized by graphics updated live. System Monitor always tries not to interfere with the activity of your computer as far as possible, and also respects the energy saver settings for your hard drives.
Additional features available after adding System Monitor Plus
Apple no longer permits that the features listed below can be part of Apps distributed via the Mac App Store. However, you can enable these functions again by downloading our application System Monitor Plus and copying it onto your computer. System Monitor Plus is available for free.
- Display of the top 5 processes currently putting the most load on the system
- Characteristic CPU temperature, measured as close to the first processor as possible
- Revolution speeds of all air blowers which are controlled by the computer
- Other sensor values acquired by Intel® Power Gadget, if installed on your Mac (for Intel-based Macs only)
- Selected temperature sensor values for Macs with Apple Silicon
- Display of the top 5 processes which consume the largest parts of the memory
After copying System Monitor Plus onto your computer, you only need to confirm in System Monitor preferences that you like to use the add-on.