# How to change the refresh rate on a Mac

> Change your Mac display refresh rate in System Settings. Learn how to enable ProMotion 120Hz or lock 48Hz and 50Hz cinema rates for judder-free video.

Published 2026-10-31 · Motion · https://www.hazenstudio.com/maclc/blog/how-to-change-refresh-rate-on-mac/

## In short

- Change display refresh rates directly in System Settings › Displays under the Refresh Rate pop-up menu.
- MacBook Pro Liquid Retina XDR displays allow you to toggle between dynamic ProMotion (24–120 Hz) and fixed cinema modes (47.95 Hz, 48 Hz, 50 Hz, 60 Hz).
- Locking your display to 48.00 Hz or 47.95 Hz eliminates 3:2 pulldown judder and clock drift frame drops for 24 fps and 23.976 fps movies.
- External monitors require high-bandwidth USB-C to DisplayPort or HDMI 2.1 connections to unlock 120 Hz, 144 Hz, or Variable Refresh Rate (VRR).

To change the refresh rate on a Mac, open the Apple menu (), select **System Settings**, click **Displays** in the sidebar, select your screen, and choose your preferred frequency from the **Refresh Rate** pop-up menu. On Apple Silicon MacBook Pro models with Liquid Retina XDR displays or the Apple Pro Display XDR, you can choose between dynamic ProMotion (24 Hz to 120 Hz) or fixed cinema rates including 47.95 Hz, 48 Hz, 50 Hz, 59.94 Hz, and 60 Hz.

While most Mac users keep their displays set to ProMotion or 60 Hz for fluid desktop scrolling, switching to dedicated fixed refresh rates is a useful technique for video editors and movie enthusiasts. Locking your display to an exact integer multiple of your video file eliminates telecine judder and prevents subtle audio sync drift.

## How to change the refresh rate in macOS System Settings

According to [Apple's official display configuration guide](https://support.apple.com/en-us/102297), adjusting the refresh rate on compatible built-in screens and external displays requires only a few clicks:

1. Open the **Apple menu ()** at the top-left corner of your screen and select **System Settings**.
2. Click **Displays** in the left navigation sidebar.
3. If you have multiple displays connected, click the icon representing the display you want to configure at the top of the window.
4. Locate the **Refresh Rate** pop-up menu on the right side of the window.
5. Click the menu and select your desired frequency.

On a 14-inch or 16-inch MacBook Pro with Apple Silicon (M1 Pro/Max through M4 family chips), the default selection is **ProMotion**. ProMotion dynamically scales panel timing between 24 Hz and 120 Hz based on what you are doing.

Below ProMotion, macOS lists five fixed reference frequencies:

- **60 Hertz:** Standard computing rate for external monitors and web browsing.
- **59.94 Hertz:** Matches American NTSC broadcast standards (`60 × 1,000 ÷ 1,001`).
- **50 Hertz:** Matches European PAL television broadcasts (25 fps / 50 fps).
- **48 Hertz:** Matches standard 24.000 fps digital cinema files.
- **47.95 Hertz:** Matches fractional 23.976 fps film transfers (`48 × 1,000 ÷ 1,001`).

On standard MacBook Air models, 24-inch iMacs, and the Apple Studio Display, the internal panel operates at a fixed 60 Hz hardware clock, meaning the Refresh Rate drop-down menu is omitted from System Settings.

## How to enable 120Hz or VRR on an external monitor

If you connect an external high-refresh-rate gaming monitor or 4K television to your Mac, enabling 120 Hz, 144 Hz, or Variable Refresh Rate (VRR) depends heavily on the physical cable and port protocol you use.

As outlined in [Apple's Adaptive Sync support documentation](https://support.apple.com/en-us/102140), macOS Monterey 12 and later supports VESA Adaptive-Sync across all Apple Silicon Macs. For dedicated computer monitors, Apple specifically recommends connecting via a USB-C to DisplayPort cable or a native Thunderbolt cable. Standard DisplayPort Alt Mode over USB-C provides the cleanest communication handshake for high refresh rates and variable sync.

To unlock high refresh rates on an external display:

1. Connect the monitor directly to your Mac using a certified DisplayPort 1.4 or Thunderbolt 4 cable.
2. In the monitor's built-in on-screen display (OSD) hardware menu, verify that **DisplayPort 1.4**, **FreeSync**, or **Adaptive-Sync** is turned on.
3. Open **System Settings › Displays** and select the external monitor thumbnail.
4. Click the **Refresh Rate** menu and choose **120 Hertz**, **144 Hertz**, or **Variable (40–144 Hz)**.

If the high-refresh-rate options do not appear:
- Hold down the **Option (⌥)** key while clicking the display resolution thumbnail or menu to reveal advanced timing options.
- If you are connecting a TV over HDMI, verify that your Mac features an HDMI 2.1 port (available on M2 Pro/Max, M3 Pro/Max, and M4 family Macs) and that you are using an Ultra High Speed 48 Gbps HDMI cable. Older Macs with HDMI 2.0 ports are capped at 4K at 60 Hz over HDMI.

To understand the difference between high fixed rates and variable syncing, explore our comparison of [120Hz vs 60Hz displays](/maclc/blog/120hz-vs-60hz/) and our explainer on [what is VRR](/maclc/blog/what-is-vrr/).

## Why does macOS offer 47.95 Hz and 48 Hz cinema refresh rates?

Many Mac users wonder why Apple includes two separate 48 Hz settings in macOS display options: 48.00 Hertz and 47.95 Hertz.

This distinction exists because of the historical divide between cinema projectors and broadcast television:

1. **True 24.000 fps:** Theatrical movies, international digital cinema packages (DCPs), and modern prestige streaming productions are captured at exactly 24.000 frames per second.
2. **Fractional 23.976 fps:** When American NTSC color television launched in 1953, engineers slowed video transmission by 0.1 percent (`1,000 ÷ 1,001`) to avoid audio carrier interference (learn more in our analysis of [23.976 vs 24 fps](/maclc/blog/23-976-vs-24-fps/)). Feature films transferred to DVD, Blu-ray, and streaming broadcast were slowed down to `24 × (1,000 ÷ 1,001) = 23.976` frames per second.

If you watch a 23.976 fps movie on a screen locked to exactly 48.00 Hz or 60.00 Hz:

`48.000 ÷ (24,000 ÷ 1,001) = 2.002`

Because the screen's clock runs 0.1 percent faster than the video file, the audio and video timestamps gradually drift apart. To maintain lip-sync, the media player is forced to duplicate or drop an entire video frame approximately once every 41.7 seconds. During slow camera pans, this drop appears as an annoying periodic stutter.

By selecting **47.95 Hertz** (`2 × 23.976 = 47.952 Hz`), you lock the display panel to the exact mathematical timing of the video stream. Every frame flashes twice (2:2 pulldown) with zero telecine judder and zero 41-second clock drift, replicating the dual-bladed shutter of an authentic 35mm film projector.

To see why mismatched cadences cause visual stutter, review our technical guide to [24 fps judder on 60 Hz screens](/maclc/blog/24fps-judder/).

## When should you switch your Mac display to 50 Hz?

In Europe, the United Kingdom, Australia, and parts of Asia, television broadcasting was built on the PAL and SECAM standards, which run at 50 fields (or 25 frames) per second, synchronized with 50 Hz AC electrical grids according to [Recommendation ITU-R BT.601](https://www.itu.int/rec/R-REC-BT.601).

When you watch European broadcast content—such as BBC television dramas, European sports matches, or British documentaries—on a standard 60 Hz computer monitor, the frame rate mismatch creates severe motion stutter:

`60 ÷ 25 = 2.4 refreshes per frame`

To display 25 fps video on a 60 Hz screen, the display system must alternate between displaying frames for 2 refreshes (33.3 ms) and 3 refreshes (50.0 ms) in an uneven 2:3 cadence. Every camera pan stumbles across the screen.

Switching your Mac's display to **50.00 Hertz** solves this problem instantly:

`50 ÷ 25 = 2.0 display refreshes per frame`

Each frame is shown for exactly two refreshes (40.0 milliseconds), delivering uniform 2:2 cadence. For a detailed breakdown of international broadcast standards, read our comparison of [50Hz vs 60Hz video playback](/maclc/blog/50hz-vs-60hz/).

MacLC, the free media player from Hazen Studio, does not alter your macOS display refresh rate. Instead, its optional motion engine can interpolate 24 fps and 25 fps video up to the display's refresh rate, stepping down rather than dropping frames if the Mac is under load.

## Why does desktop scrolling feel sluggish at 48 Hz or 50 Hz?

While locking your MacBook Pro to 48 Hz or 50 Hz creates smooth movie playback, you will immediately notice that your mouse cursor feels laggy and web browsing looks choppy the moment you exit the video player.

At 120 Hz, your screen draws a new image every 8.33 milliseconds. At 48 Hz, that interval expands to 20.83 milliseconds—more than double the latency. Text blurs heavily when scrolling through documents, and window animations lose their crispness.

Treat 47.95 Hz, 48 Hz, and 50 Hz as dedicated cinema reference modes. When your movie or editing session ends, return to System Settings › Displays and switch the Refresh Rate menu back to ProMotion (or 60 Hz on fixed external panels) to restore snappy desktop responsiveness.

## What to do if your external monitor is stuck at 30Hz or 60Hz

If you connect a high-refresh-rate external display but the Refresh Rate menu in macOS only lists 30 Hz or 60 Hz, check these four common hardware bottlenecks:

1. **USB-C Hub or Dock Limits:** Many budget multi-port USB-C dongles only support HDMI 1.4 or DisplayPort 1.2, which caps 4K video at 30 Hz. Ensure your hub or dock explicitly advertises DisplayPort 1.4 (DP Alt Mode) or HDMI 2.0/2.1 with 4K at 60 Hz / 120 Hz support.
2. **HDMI Cable Bandwidth:** Standard HDMI cables cannot carry 4K at 120 Hz. You need a certified Ultra High Speed (48 Gbps) HDMI cable connected to a Mac with native HDMI 2.1 ports.
3. **Monitor Port Settings:** Some monitors ship with DisplayPort set to version 1.1 or 1.2 by default in their hardware OSD settings for backward compatibility. Use the monitor's physical buttons to change the port version to DisplayPort 1.4 or 2.1.
4. **macOS Display Mirroring:** If your external monitor is mirroring your MacBook's built-in screen, macOS synchronizes both screens to a common denominator (often 60 Hz). Open **System Settings › Displays** and set the external display to **Stop Mirroring** or **Extended Display**.

If your screen cannot be set to a matching cinema refresh rate, you can also consider software solutions like [motion interpolation](/maclc/blog/motion-interpolation/) to bridge frame rate gaps cleanly.

## Tailoring your Mac display for cinema

macOS provides video creators and film lovers with fine-grained control over panel timing. By navigating to System Settings › Displays, you can switch between dynamic ProMotion for daily work and dedicated 47.95 Hz, 48 Hz, or 50 Hz cinema cadences for movie night.

Matching your display's refresh rate to the exact frame rate of your media eliminates telecine judder, prevents frame-dropping glitches, and ensures you experience every film exactly as the director framed it.

## Questions people ask

### Where is the refresh rate setting on a Mac?

Open System Settings from the Apple menu (), click Displays in the sidebar, click your display thumbnail, and select the desired frequency from the Refresh Rate pop-up menu located in the lower-right area of the pane.

### Why should I change my Mac screen to 48 Hz for movies?

Standard 60 Hz screens cause 3:2 pulldown judder on 24 fps films. Setting a MacBook Pro or Pro Display XDR to 48.00 Hz creates a 2:2 cadence, showing every film frame for exactly two screen refreshes and eliminating pan stutter.

### What is the difference between 47.95 Hz and 48 Hz in macOS?

48.00 Hz matches true integer 24.000 fps theatrical movies. 47.95 Hz matches fractional 23.976 fps (24000/1001) film transfers common on Blu-ray and streaming services, preventing a frame drop or repeat every 41 seconds.

### Can I enable 120Hz on an external monitor with a Mac?

Yes, provided your monitor supports 120 Hz or higher and is connected via a compatible cable. Apple recommends USB-C to DisplayPort or Thunderbolt cables for PC monitors, or an Ultra High Speed HDMI cable on Macs equipped with HDMI 2.1 ports.

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