Frame Rate

Frame rate describes how many individual still images are displayed in each second of a moving image. Each frame is a single still picture, and playing many of them quickly one after another creates the illusion of movement. Frame rate is measured in frames per second (fps).

What the numbers mean

A clip at 30 fps shows 30 separate pictures every second. Raise it to 60 fps and you show 60, so each second is split into twice as many moments. Because every frame stays on screen for less time, a moving subject is caught in smaller steps from one frame to the next.

For example, a pupil waving at the camera at 15 fps might see their hand jump to a new position between frames, so the wave looks jerky. Film the same wave at 60 fps and the gaps between positions are tiny, so the hand moves smoothly.

Smoother motion

Higher frame rates produce smoother motion. The extra frames fill in the movement, so your eye sees a continuous flow rather than a series of separate pictures. A low frame rate can make quick movement look jerky, and a fast object may seem to jump from place to place rather than glide across the screen.

Fast movement needs more frames

When things move quickly, a fast frame rate matters more. A clip of a bee darting between foxgloves, a dog shaking water from its coat or a chef tossing a pancake in a pan all change position a lot from moment to moment. Plenty of frames each second keeps that action smooth instead of choppy, and helps you spot the detail of what happened. Fast frame rates are important for fast-moving content, because there is more change to capture between frames.

Frame rate is not the same as resolution. Resolution is about the number of pixels in each frame, while frame rate describes how many frames you see every second.