Hawk-Eye Shot Stats (Speed, Spin RPM, Depth)
Also known as: Hawk-Eye stats, Hawk-Eye spin stats, ball tracking stats tennis, spin rpm, spin rpm tennis, shot speed stats, net clearance stat, shot depth stats, shot quality score
Hawk-Eye uses cameras to track the ball in 3D, and broadcasts turn that into shot stats. Speed is how fast the ball travels, in mph or km/h. Spin is how fast it rotates, in revolutions per minute (rpm). Net clearance is how high the ball passes over the net, and depth is how close to the baseline it lands. Treat spin figures as estimates.
Hawk-Eye is a camera-based ball-tracking system used at big events. Along with line calling, its data feeds the stats you see on TV and in match reports.
Each stat describes a part of the shot. Speed is usually shown for serves and groundstrokes, in mph or km/h. Spin, in rpm, shows how much the ball rotates. More topspin makes the ball dip and kick up higher. Net clearance is the height over the net. A higher clearance gives more margin. Depth shows where the ball lands, and deep balls push opponents back.
Some broadcasts combine these into a shot quality score. The LTA describes it as a score from 0 to 10 based on spin, speed, depth and width. It can be given for forehands, backhands, serves and returns.
Read spin numbers with care. Researchers note that the precision of the proprietary spin figures is not well understood. Use them to compare shots within one match rather than as exact values.
Tips by skill level
When watching pros, notice how high many of their groundstrokes clear the net. That margin is part of their consistency.
Match a pro's numbers to the shot's purpose. Deep, high-clearance balls build points, while flatter, faster ones finish them.
Example
On TV, a player's forehand shows high spin and high net clearance but a modest speed. That pattern means a heavy, safe topspin ball that lands deep.
Why it matters
These stats explain why some shots cause trouble even when they aren't fast. They also show the mix of speed, spin and margin you can aim for in your own game.
Common mistakes
- Judging a shot by speed alone
- Treating broadcast spin figures as exact measurements
- Ignoring net clearance, which shows how much margin a shot had
Frequently asked questions
What does spin rpm mean in tennis?
It is how many times the ball rotates per minute. Higher topspin rpm makes the ball dip faster and bounce higher.
What is shot quality in tennis stats?
A score from 0 to 10 that rates a shot from its spin, speed, depth and width, based on ball-tracking data.
How accurate are Hawk-Eye spin numbers?
Treat them as estimates. Researchers say the precision of the proprietary spin figures is not well understood.
Sources
- LTA — Tennis Stats Explained: Shot quality (0–10 from spin, speed, depth and width); Fastest serve (km/h or mph); FAQ on Hawk-Eye ball tracking
- Cant O. Exploring the effects of ball speed and spin in Grand Slam tennis match-play. PhD thesis, Victoria University (abstract: precision of proprietary Hawk-Eye spin measures not well understood)
Related terms
- Challenge System (Line Calls)The challenge system lets a player dispute a line call using electronic ball-tracking. Only a limited number of unsuccessful challenges are allowed per set.
- TopspinTopspin is forward spin imparted by brushing up the back of the ball. It makes the ball dip down into the court and kick up high after the bounce.
- Net ClearanceNet clearance is how high your shot passes over the net. The net is 3 feet (0.914 m) high at the centre and 3½ feet (1.07 m) at the posts (ITF Rule 1). Rally balls with topspin can pass well above the tape and still land deep. Keep low clearance for passing shots, attacking balls and shots hit from close to the net.
- Depth ControlTo hit deeper, aim higher over the net instead of hitting harder. Swing low to high, extend the racquet toward the target and let topspin bring the ball down near the baseline. Short balls often clear the net too low or come from a cut-off follow-through.
- Rally LengthRally length is the number of shots in a point from serve to finish, a tactical metric that reveals whether a player wins most points early (0–4 shots), in mid-length rallies (5–8), or in extended exchanges (9+).
Related guides & benchmarks
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