Grant is estimated to earn approximately $150,000 a year. He is sponsored by Westpac, Qantas and uncle Toby's - his photo is on their Sports Plus cereal pack.
Grant owns a $56,000, canary yellow Holden, which is capable of doing up to 300km/h.
Grant celebrated his 18th birthday at Melbourne's Crown Casino.
At Dreamworld, on the Gold Coast, there is a koala named after Grant, and is called Hackett.
When Grant was 10 he was going for his S badge, for surf lifesaving Nippers, with a group of other Nippers to prove they were strong enough to enter surf races. They was a big rip and none of the other kids made it except for Grant. The examiner didn't believe him so he did it again.
Grant is planning to go into property development.
When Grant was 14 he convinced his brother to lend him his car. Grant was out driving the car when his dad saw him. Grant came home but before his dad got home, left and disappeared for days.
Grant lives in the "Granny Flat" at the back of his parents house. In it he has a black-satiny bed cover, an Akai vision and sound system, five piece drum kit, a Fender guitar and Marshall amp, on the walls there is a charging African lion poster and an HSV poster signed by Mark Skaife and Craig Lowndes.
Grant was allergic to dust and continually staying in badly ventilated hotel rooms didn't help him. His dad, Nev built him a room in the house that was tiled with no carpet. To stop his immune system running down Grant changed his diet. His mum, Margaret says "he was a real garbage guts before, heaps of chocolate and soft drinks. Now it's dairy, light soy milk on his cereal - 20 bowls a day though he's cut down now since being told it's too much."
Craig, Grant's brother, did a test on Grant and found he could only bench press 40kg, while Susie O'Neill could press 50kg. After 3 months of training he has got up to 80kgs. "His 200m world record was the first we knew we succeeded," says Craig.
Grant played the guitar on hey Hey It's Saturday. He played with the Hey Hey band and they played 'Purple Haze' by Jimmy Hendricks (?)
At the beginning of '99 Grant went to Canada for 'a change of atmosphere and something a little bit different.'
There is a car called the Hackett Gold, a special edition Holden, named after Grant Hackett, Grant owns one.
Grant has never lost to Kieren Perkins in a major event.
Grant's favourite CD is Garbage, Version 2.0
Grant says his worst bedroom habit is playing his music too loudly and describes his bedroom as fun, noisy and happy.
