Hawk-Eye: Tennis’ greatest innovation that keeps Wimbledon’s umpires on their toes

If you’ve watched any of Wimbledon 2015 you will have seen that Hawk-Eye is used in almost every set played on the famous grass courts of SW19. It is the first and only ball-tracking technology to have passed the stringent testing measures set out by the International Tennis Federation (ITF) and is now a key part of the ATP, WTA and ITF tennis tours. To pass the ITF tests the system needs to have an error of less than 5mm, however today’s Hawk-Eye systems usually operates with an error of less than 3mm.

Over the course of a year roughly 30 per cent of the challenges by players disprove the original call, which can change the outcome of a match in the short term, but potentially influence the success of a player’s career in the long run.

Hawk-Eye: Tennis' greatest innovation that keeps Wimbledon's umpires on their toes
Once a player has challenged a call, it will be displayed on the big screen inside the stadium and on TV screens around the world.

The technology works by tracking every shot of every point using 10 high speed cameras, capturing high-resolution images at 60 frames per second (double the speed of an average TV camera). 5 cameras are placed at each end of a tennis court, and are positioned so that they are in line with each line on the court. These cameras are triangulated so that they can provide the 3D location of any shot, using complex mathematical equations to determine the balls exact position.

Any shot that is close to being in or out is immediately checked by the Hawk-Eye operators, so that when a call is challenged they are ready to send it to the big screen and to TV feeds so that both the players and spectators can see whether the ball was in or out. After each point, the quality of the tracking by each camera is checked by the operators, so that any adjustments to improve the tracking quality can be made.


Hawk-eye operates at nearly every major tennis tournament around the world, which allows them to gather data from different surfaces and compare them.

On the whole the players are a fan of the system, Andy Murray was quoted as saying that he loves it. An example of its importance was clear to see during his 4th round match versus Ivo Karlovic, in which a vital Hawk-Eye challenge overturned a call that could have resulted in Murray facing the perils of a 5th set against the giant Croatian.

Hawk-Eyes main objective is to function in an official line calling capacity, but it goes much further than that. It has made a huge contribution to broadcasting by providing unparalleled statistical analysis, which can be viewed in a dynamic and exciting way using its virtual reality software. Simple stats such as serve direction can be quickly shown to TV audiences, as well as more detailed analysis such as comparing a players forehand at this year’s Wimbledon with their forehand at last year’s tournament.

Hawk-Eye now has the ability to show statistics over live video, adding another dimension to their contribution to the sport.

Tennis is not the only sport that benefits from Hawk-Eye’s involvement, it is used in cricket, football, snooker and baseball to name a few, and is constantly moving into new sports around the world. Improvements in accuracy will continue to be seen in the coming years, as will new ways for TV audiences to engage with this brilliant technology. “Ultra-motion,” which involves showing the challenge over real footage of the match rather than in Hawk-Eye’s reality world is now being rolled out across a number of global tennis events, and is likely to become the norm in years to come.

Make sure you look out for Hawk-Eye’s involvement in the final few matches of this year’s Wimbledon, it’s likely to be called upon more than ever as the best players in the world battle for the most coveted Grand Slam title.


Discover more amazing facts in the latest issue of How It Works magazine. It’s available from all good retailers, or you can order it online from the ImagineShop. If you have a tablet or smartphone, you can also download the digital version onto your iOS or Android device. To make sure you never miss an issue of How It Works magazine, make sure you subscribe today!


Plus, take a look at:

Win a Zepp Tennis Sensor

How does the Wimbledon roof work?

What’s the science behind Andy Murray’s serve?