Phantasmic is system menubar application that monitors the temperature sensors of your Macintosh computer and optionally allows you to control the system fan(s).

There is no icon in the Dock, but instead a menu is added to the system menubar displaying a temperature and fan speed.

If you click on this menu you will see a number of commands allowing you to view more detailed information.

On first run you will be prompted for your system administrator credentials. Phantasmic requires a small privileged helper program to make adjustments to the hardware settings.

Default Operation

By default, Phantasmic operates in a monitor mode and makes no adjustments to your system fans, simply reporting the readings from the various sensors built into your Macintosh hardware.

RPM/Temperature Tracking

Fan adjustment is enabled by checking the 'Modify Fan' checkbox.

When controlling the fans you can choose either set the fan to constant speed, or alternatively allow variable speed, tracking a selected temperature sensor between an upper and lower value.

If you choose to use variable speed then you must also use one of the other three methods to track the temperature. Each method will realise the same fan speeds at the temperature endpoints but will have slightly different tracking characteristics between the two settings. In all cases the fan will not go faster than the maximum value or slower than the minimum value (except for some minor overshoot in either direction).

Constant RPM The temperature endpoints are ignored and Phantasmic attempts to maintain the fan speed at the setting you have provided.
If this setting is too low then your Macintosh may overheat.
If it is higher than required you are prematurely wearing out your fan and your machine may be noisier.
You can only set a speed that lies between the hardware defined minimum and maximum speed limits for the fan.
NormalThe fan speed is changed in direct proportion to the monitored temperature sensor.
CoolerTracking is via a logarithmic relationship. The fan will run faster than with the Normal relationship.
WarmerTracking is via an exponential relationship. The fan will run slower than with the Normal relationship..

Restoring System Defaults

When you Quit Phantasmic, all modified settings are returned to their system defaults.

When you switch off Fan Adjustment mode, all modified settings are returned to their system defaults.

The menu item Reset to System Defaults deletes all your preferences and restarts Phantasmic as though it were running for the first time.

How is Phantasmic better than the standard system firmware?
  • For many people there is no advantage. However, even if you don't want to control the fans, Phantasmic is a useful monitor of your system hardware.
  • If you find your system fans are excessively noisy, Phantasmic enables you to investigate the cause by viewing the temperatures of the hardware components that generate heat within the machine. This may point to faulty hardware or to unexpectedly high workload.
  • In some models of Macintosh, replacement of the hardware with non-Apple components (e.g. disk drives) can result in the fans running continually at full speed. Phantasmic enables you to regain control of the fans
  • Some models of Macintosh seem to get really warm before the fans kick in. You can use Phantasmic to have the fans start at a lower temperature


Download Phantasmic 1.4.0

Phantasmic 1.4.0 - Changes and Features


  • Only available for macOS 10.13 or later.
  • Updated to Sparkle 2.5.0.
  • Compile with Xcode 15.0.


  • Fix ruler clipping in macOS Sonoma.

Download Phantasmic 1.3.3

Phantasmic 1.3.3 - Changes and Features


  • Use PID controller to adjust the fan speed.
  • Updated to Sparkle 2.2.2.
  • Compile with Xcode 13.4.1.


  • Validate all configured fans are present in hardware.


Download Phantasmic 1.3.2

Phantasmic 1.3.2 - Changes and Features


  • Use sigmoid curve segments for Warmer and Cooler responses
  • Embed new command line tool fanutil.
  • Embed new command line tool arm64sensors.
  • Export command line utilities.
  • Documentation update for command line utilities

Download Phantasmic 1.3.1

Phantasmic 1.3.1 - Changes and Features


  • arm64 - do not set SMC fan mode unless it has changed.
  • x86_64/arm64 - Added log entry when SMC mode changes.
  • x86_64/arm64 - Fix ruler update when window content is scrolled.

Download Phantasmic 1.3.0

Phantasmic 1.3.0 - Changes and Features


  • Compile with Xcode 13.2.1
  • Use Sparkle 2.0.0 for updates.
  • Runs native with fan control on Apple Silicon.

Download Phantasmic 1.2.11

Phantasmic 1.2.11 - Changes and Features


  • Compile with Xcode 12.0
  • Menubar - fixed for Big Sur (macOS 11)

Download Phantasmic 1.2.10

Phantasmic 1.2.10 - Changes and Features


  • Exclude spurious CPU temperatures keys on older Mac Mini.

Download Phantasmic 1.2.9

Phantasmic 1.2.9 - Changes and Features


  • Menubar text colour indicates the machines thermal state.


  • Fan min and max rpm may be changed by SMC.

Download Phantasmic 1.2.8

Phantasmic 1.2.8 - Changes and Features


  • French localisation - thank you Jean-Pierre Kuypers.
  • Show Standard Deviation bounds on Temperature graph.

Download Phantasmic 1.2.7

Phantasmic 1.2.7 - Changes and Features


  • Compile with Xcode 11.1, Swift 5.1
  • Show fan start/stop limits on the Temperature graph.
  • Remove PID control and use smoothed temperature to control fan speed.
  • Add menu for changing fan and temperature sensor colours.
  • Allow user to change and view thermal model settings when running as a monitor.

Download Phantasmic 1.2.6

Phantasmic 1.2.6 - Changes and Features


  • Compile with Xcode 10.2, Swift 5

Download Phantasmic 1.2.5

Phantasmic 1.2.5 - Changes and Features


  • Backward compatible with OS X 10.10 (Yosemite).
  • Sparkle updated to version 1.21.2.
  • Relaunch Phantasmic if it has been translocated.

Download Phantasmic 1.2.4

Phantasmic 1.2.4 - Changes and Features


  • Icon/Single line/Double line menubar display.


  • PID icon visibility in dark mode.
  • Menu text visibility in dark mode.

Download Phantasmic 1.2.2

Phantasmic 1.2.2 - Changes and Features


  • Phantasmic is now notarized by Apple.

Download Phantasmic 1.2.1

Phantasmic 1.2.1 - Changes and Features


  • Compiled with Xcode 10, Swift 4.2.

Download Phantasmic 1.2.0

Phantasmic 1.2.0 - Changes and Features


  • Show fan speed limits on RPM graph.
  • Add thermometer icon to sensor image.
  • Added Warmer/Cooler (sigmoid) rpm/temperature relationship.
  • Added PID controller (optional).
  • Added Preference setting for fan speed tolerance.
  • Refactoring of internal frameworks.


Download Phantasmic 1.1.0

Phantasmic 1.1.0 - Changes and Features


  • Added graphs for 'fan rpm vs time' and 'sensor temperature vs time'.
  • Added Help button to each window.
  • Regrouped menu commands.
  • Added menu commands for opening/closing all windows.
  • Show the main window automatically when first running a new version.
  • Option to display temperature in degrees F (default is degrees C).
  • Efficiency improvement in scanning sensors.
  • Coarser exponential algorithm for 'Warmer' setting.

Download Phantasmic 1.0.0

Phantasmic 1.0.0 - Changes and Features
  • First public release