# How to control fan speed on a Mac

Canonical page: https://vitalsmac.com/mac-fan-control

By Atta Ur Rehman Shah, maker of Vitals. Published September 30, 2026.

**Short answer:** macOS does not let you set fan speed: there is no slider in System Settings and no Terminal command, because the Mac sets its fans from its temperatures. The closest built-in control is Energy Mode, in System Settings → Battery (Energy on a desktop Mac): Low Power Mode helps keep the fans quiet, and High Power Mode, on some MacBook Pro, Mac mini and Mac Studio models, lets them run faster. To choose a fan’s speed yourself, you need a fan control app. Vitals, a system monitor for the Mac, does it on every Mac with fans, M1 to M5 included, in the same place it shows the temperatures: switch a fan from Auto to Set, drag it to the speed you want, and switch it back to Auto to hand it to the Mac.

## How to change fan speed on a Mac

1. Open System Settings → Battery on a MacBook, or System Settings → Energy on a desktop Mac.
2. Under Energy Mode, choose Low Power Mode for quieter fans, or High Power Mode, where your Mac offers it, to let the fans run faster during long, heavy work. On a MacBook, set On power adapter and On battery separately.
3. To choose an exact speed, open a fan control app, pick a fan, switch it from automatic to a fixed speed, and set the speed in revolutions per minute (rpm).
4. Hand the fan back to automatic when the heavy work ends. A fan held at a fixed speed stays there whatever the temperature.

MacBook Air models with Apple silicon have no fan, so there is nothing to set. They slow down to cool off instead.

Every Mac with a fan runs it on a [fan curve](https://vitalsmac.com/glossary/fan-curve): faster as the temperatures rise, slower as they fall, between a lowest and a highest speed set for each fan. macOS shows neither the speed nor the curve. A fan control app writes to the System Management Controller (SMC), the chip that runs the fans, to hold a fan at the speed you choose. The table below says when that helps, and when to look for the cause of the heat instead.

## When to change a Mac’s fan speed

| Situation | What to do | Why |
|---|---|---|
| A long export, build or render | Raise the fans before you start, or use High Power Mode | A cooler chip keeps its full speed longer before macOS slows it down |
| A game or a local AI model on a MacBook Pro | Raise the fans | Less [thermal throttling](https://vitalsmac.com/glossary/thermal-throttling), at the cost of noise |
| A hot room, or a Mac on your lap | Raise the fans, and clear the vents | The Mac starts closer to the temperature where it slows down |
| Light work in a quiet room | Low Power Mode | Less heat, so the fans stay slow on their own |
| Fans loud while you do little | Find the app heating the Mac first | The fans are answering real heat; see [why a Mac’s fans get loud](https://vitalsmac.com/mac-fan-loud) |
| Fans at full speed with nothing busy | Run Apple Diagnostics | A fan or sensor fault, which a fan control app only hides |

## Is it safe to control a Mac’s fans?

Raising the speed is safe. The chip runs cooler and holds its full speed for longer; the costs are noise, and a little battery on a MacBook.

Lowering the speed is where the risk is. A fan held slow while the chip heats up cannot remove the heat, so macOS slows the chip down to protect it: the Mac stays safe, and gets slower. A careful fan control app keeps each fan within the lowest and highest speed the Mac allows, but a fan can still be held at its lowest while the Mac works hard. Set a low speed only for light work, and hand the fan back to automatic before anything heavy.

## How fan control apps work

The SMC keeps two settings for each fan: a mode, automatic or manual, and a target speed. An app sets the target and switches the fan to manual; switching it back to automatic hands the fan to macOS again. Only a process running as root may write to the SMC, so fan control apps install a small helper that macOS asks you to approve.

The Mac takes its fans back when it sleeps, so a fan control app has to set them again when it wakes. Apps differ in what they set: some hold a fixed speed, and some, such as Macs Fan Control, can also follow a temperature sensor.

On Macs with M3 and M4 chips, macOS’s thermal manager holds the fans and refuses a manual setting until an app asks it to step aside. That is why some fan control apps show the speed on those Macs but cannot change it. Before you rely on one, check that it supports your Mac’s chip.

## Fan speed and rpm

Fan speed is measured in revolutions per minute (rpm). Each fan has its own lowest and highest speed, which differ from model to model, so the same figure can be quiet on one Mac and loud on another. What matters is where the fan sits between its own two limits.

At rest, a Mac’s fans run at or near their lowest speed, and some Apple silicon Macs stop them entirely when cool. Under load they climb toward their highest. If they stay high after the work ends, something is still working the chip: [find the app heating the Mac](https://vitalsmac.com/mac-fan-loud) before you change the speed.

## What Vitals adds

Vitals sets each fan’s speed in the same place it shows the temperatures.

- Temperature & Fans, from Sensors in the menu bar dropdown: each fan’s speed in rpm, with Auto and Set beside it
- Set, then drag: any speed between that fan’s own lowest and highest, in steps of 50 rpm. Auto hands one fan back, Back to Automatic every fan at once
- A fan you set stays set through sleep and restarts until you hand it back, and every fan goes back to the Mac when Vitals quits, or if it crashes
- Keeping the Fans On, above the fans, names the apps heating the Mac, with Quit beside each
- Apple silicon from M1 to M5, and Intel Macs

Good to know:

- Setting a fan uses Full System Metrics, the helper Vitals also uses to read system processes. macOS asks you to approve it once, in Login Items.
- On M3 and M4, Vitals first asks macOS’s thermal manager to step aside, so the first setting takes a few seconds.
- Vitals keeps a fan between its own lowest and highest speed. It writes only the fan’s mode and target speed, plus, on M3 and M4, the one key that asks the thermal manager to step aside.
- A set fan holds its speed whatever the temperature. Vitals does not follow a sensor or a custom curve.
- If the Mac does not take a setting, the fan’s row says so, and the fan stays with the Mac.

Vitals is $9 during the launch, $29 after it, once: [vitalsmac.com](https://vitalsmac.com/).

## Questions people ask

### Can you control fan speed on a Mac?

Not with macOS itself. Energy Mode in System Settings changes how hard the fans work, and a fan control app such as Vitals sets an exact speed for each fan.

### How do I make my Mac’s fans run faster?

Choose High Power Mode in System Settings → Battery, if your Mac offers it, or set the fan’s speed in a fan control app. In Vitals, click Sensors in the menu bar dropdown, switch the fan to Set and drag it up.

### Is it safe to increase fan speed on a MacBook?

Yes. A faster fan keeps the chip cooler; the costs are noise and a little battery. Lowering the speed during heavy work is what makes the Mac slow itself down.

### Does fan control work on Apple silicon Macs?

Yes, on Apple silicon Macs that have fans, with an app that supports your chip. On M3 and M4, the app has to ask macOS’s thermal manager to step aside before a setting holds. Vitals does, and works from M1 to M5. MacBook Air models with Apple silicon have no fan.

### Can I control fan speed on an M3 or M4 Mac?

Yes, with an app that supports those chips. On M3 and M4, macOS’s thermal manager refuses a manual fan speed until the app asks it to step aside; apps that do not ask show the speed but cannot change it. Vitals asks, and the first setting takes a few seconds.

### How do I reset my Mac’s fans to automatic?

Switch each fan back to automatic in the app that set it. In Vitals, click Back to Automatic under the fans, or quit Vitals, which hands every fan back to the Mac.

### What is a normal fan speed on a Mac?

It depends on the model, since each fan has its own lowest and highest speed. At rest the fans run at or near their lowest, and they speed up under load. Vitals shows each fan’s speed and how close it is to its highest.

In the glossary: [Fan curve](https://vitalsmac.com/glossary/fan-curve), [Thermal throttling](https://vitalsmac.com/glossary/thermal-throttling), [kernel_task](https://vitalsmac.com/glossary/kernel-task), [% CPU](https://vitalsmac.com/glossary/cpu-percent), [% GPU](https://vitalsmac.com/glossary/gpu-percent).

More guides: [Why is my Mac so slow](https://vitalsmac.com/why-is-my-mac-so-slow), [What’s draining my Mac’s battery](https://vitalsmac.com/mac-battery-draining-fast), [Which app is using my CPU or memory](https://vitalsmac.com/check-cpu-memory-usage-mac), [Why won’t my Mac sleep](https://vitalsmac.com/mac-wont-sleep), [Chrome using too much memory](https://vitalsmac.com/chrome-using-too-much-memory-mac), [Why are my Mac’s fans so loud](https://vitalsmac.com/mac-fan-loud), [How to free up RAM on a Mac](https://vitalsmac.com/free-up-ram-mac), [Docker using too much memory](https://vitalsmac.com/docker-using-too-much-memory-mac), [How to stop Docker containers](https://vitalsmac.com/stop-docker-containers-mac), [Volume mixer for Mac](https://vitalsmac.com/mac-volume-mixer), [Activity Monitor alternatives](https://vitalsmac.com/best-activity-monitor-alternatives), [iStat Menus alternatives](https://vitalsmac.com/best-istat-menus-alternatives), [Stats alternatives](https://vitalsmac.com/best-stats-alternatives), [Task Manager for Mac](https://vitalsmac.com/task-manager-for-mac), [Best system monitors for Mac](https://vitalsmac.com/best-system-monitor-for-mac), [Best menu bar monitors for Mac](https://vitalsmac.com/best-menu-bar-system-monitor-for-mac), [Best volume mixers for Mac](https://vitalsmac.com/best-volume-mixer-for-mac).