Refresh Rate and Response Time Explained

Refresh rate and response time both describe motion, but they measure different things. Refresh rate, in hertz (Hz), is how many times per second the display draws a new image. Response time, in milliseconds (ms), is how quickly each pixel can change from one colour to another. For most business uses, such as signage, presentations and office work, a 60 Hz display with a reasonable response time is all you need. Higher refresh rates and faster response times matter for gaming, simulation, fast sports content and some control rooms.

Refresh rate in plain English

A 60 Hz display updates 60 times a second; a 120 Hz display 120 times. Higher rates make motion look smoother, provided the content and source actually deliver that many frames per second.

Content matters. Video is typically recorded at 24, 25, 30, 50 or 60 frames per second, and a signage loop at 30 frames per second won’t look smoother on a 120 Hz screen. In the UK and Europe, broadcast content is usually 25 or 50 frames per second, while North America uses 30 or 60, so make sure your player and display handle the rates you use without judder.

Response time in plain English

Response time is usually quoted as grey-to-grey (GtG): the time a pixel takes to shift between shades. Slow response causes smearing or ghosting behind moving objects.

• Under 5 ms: very fast; typical of gaming monitors
• 5 to 10 ms: good for general use and video
• Above 10 ms: fine for static content, but may smear with fast motion

Manufacturers measure response time in different ways and often quote the best case, so treat figures as a guide and look for independent reviews. VESA’s ClearMR certification is one attempt to rate motion clarity consistently.

Why fast screens can still blur

Most LCDs hold each frame on screen until the next one arrives, which our eyes perceive as blur when we track moving objects. Higher refresh rates reduce this, and some displays add backlight strobing or black-frame insertion to sharpen motion, at the cost of brightness. Panel type matters too: VA panels can smear in dark scenes, as explained in our guide to IPS vs VA vs TN.

Input lag: the one touchscreens care about

Input lag is the delay between a signal arriving and the image changing. It matters for:

• Touchscreens and kiosks, where a laggy response feels broken; see our guide to touchscreen kiosks for retail
• Interactive whiteboards and meeting room displays
• Gaming venues and simulators

Many displays offer a “game” or low-latency mode that switches off extra processing to reduce lag.

Variable refresh rate

Variable refresh rate (VRR) technologies, including those in HDMI 2.1 and adaptive sync standards, let the display match its refresh rate to the frames the source sends. This prevents tearing and stutter in games and interactive graphics. It’s rarely needed for signage.

LED video walls: a different kind of refresh

For LED walls, “refresh rate” often means how fast the LEDs are driven, commonly quoted in the thousands of hertz. A high driving refresh rate reduces visible flicker and prevents scan lines when the wall is filmed or photographed, which matters for broadcast studios, events and venues where guests take photos. Our guide to LED video walls and pixel pitch explains what else to compare.

What each use needs

Cables and sources

Higher refresh rates at high resolution need more bandwidth. HDMI 2.0 handles 4K at 60 Hz; 4K at 120 Hz needs HDMI 2.1 or DisplayPort, with a player or computer that supports it. Consumer streaming sticks and many signage players output 60 Hz only; see our guide to signage media players.

Frequently asked questions

Is 60 Hz good enough for digital signage?

Yes. Signage content rarely exceeds 60 frames per second, so 60 Hz displays are standard and reliable.

Is a lower response time always better?

Lower is better for motion, but beyond a point the difference is hard to see outside gaming. Manufacturers’ figures also vary in how they’re measured.

Why does my LED wall flicker on camera?

The LEDs may be driven at a refresh rate too low for the camera’s shutter speed. Walls with higher driving refresh rates, and matching camera settings, reduce the problem.