The Hawkeye system will be used throughout the Barclays Premier League season in an effort to put an end to controversies such as Roy Carroll getting away with dropping the ball into his own goal against Tottenham in 2005, and Reading's 'ghost goal' against Watford in 2008.
Hawkeye uses 14 cameras and will send a signal to the referee's watch and ear-piece indicating that the ball has crossed the line.
It will be used for the first time in Sunday's Community Shield match between Manchester United and Wigan.
Given the fine margins that can exist between success and failure or survival and relegation in the top flight, Mackay will be happy to have the system in use when his Bluebirds kick off their Premier League campaign at West Ham next weekend.
"It will only come up once every five or 10 games, but when it does it will help make those decisions clearer," he said.
"Three points can make the difference between staying up or going down and if modern technology can help then it should happen.
"One of the most important factors of football is scoring goals and it won't slow the game down that much."
But Mackay does not want to see the introduction of technology in further areas of the game.
"I think if you start bringing it in to other parts of the game then it will and it will change the spectacle," he said.
"I don't goal-line technology will slow the game down too much and goals are a massive part of football.
"I think if it goes much further then it will change the way the game is perceived."
Mackay is preparing the Bluebirds for their maiden Premier League campaign, and is working to further strengthen his squad before the end of the summer transfer window.
The Scot has already broken the club's transfer record twice this summer with the acquisitions of striker Andreas Cornelius and England defender Steven Caulker.
But Toulouse's French international midfielder Etienne Capoue will not be his third big-money signing.
Cardiff had a bid of around £9.5million accepted by the Ligue 1 club, and even agreed personal terms with the 25-year-old, but Capoue is set to move to top-flight rivals Tottenham instead.
Mackay said: ''We had a bid accepted but it looks as if he has decided, as far as I am aware, to go to Tottenham.
''It looks like it will go that way.''