Apart from the size of the panel on your TV or monitor, shown in inches, the other key number that you may find in a panels specifications is the refresh rate of the screen.
"Refresh rate" refers to the number of times per second that a screen is updated with an image. This measurement is taken in Hz. For example, a projector which changes the image 24 times per second, which is expressed as 24Hz, displays each image on the screen for 1/24th of a second.
Most TVs and monitors nowadays will have a refresh rate of 30, 60 or 120Hz, with some monitors even reaching 144Hz and above. This allows for super-smooth motion and image reproduction.
Screens will have a maximum refresh rate (usually the figure in Hz that it is advertised with), but this does not mean that every image produced by the screen will be at this rate.
This is due to different image sources and video inputs having individual native refresh rates, which the screen must adapt to accordingly.
Most TVs and monitors will automatically detect the highest possible framerate of the connected video input device and switch to suit, as you can usually determine from an on-screen prompt that appears when the device is connected.
A TV detecting a 4K-capable signal over HDMI at 60Hz, with HDR enabled and supported.
When using a computer connected to a monitor that supports higher refresh rates, you are able to manually set the refresh rate:
- Navigate to Settings > System > Display > Advance display settings
- Click on 'Display adapter properties for Display 1'
- Navigate to the 'Monitor' tab and adjust your refresh rate using the drop-down menu
- Click 'Apply' to save the setting
- Click on the 'Apple' menu and choose 'System Preferences'
- Navigate to 'Displays'
- Under the 'Display' tab, hold down the OPTION key and click on the 'Scaled' button to reveal the refresh rate options
Please note that some connections are limited in their maximum resolutions and refresh rates:
HDMI 1.4 - up to 4K@30Hz, 1600p@75Hz, 1080p@144Hz
HDMI 2.0 - up to 4K@60Hz, 1440p@144Hz, HDR
DisplayPort 1.2 - up to 4K@60Hz, 1440p@144Hz, HDR
DVI - up to 1080p@144Hz
VGA - up to 1080p@60Hz
With some TVs and monitors, there may be a small sticker on the rear or underside of the product which states “50/60Hz”, without any reference to what this is applicable to. This sticker actually denotes the power rating of the unit and is unrelated to the refresh rate of the screen itself.