A seemingly endless room behind a door at Kami's Lookout. Time passes faster inside, a year within the Hyperbolic Time Chamber is only one day outside.
Hyperbolic Time Chamber is located in Kami's lookout and the gravity is higher than Earth. It has a door entrance which separates the two dimensions of the time chamber and the outside world. Inside the chamber it has a great void that has no end or boundary stated by Goku when Gohan surprised by the havoc emptiness of the area. There are no exact day and night or any seasonal changes occur in there. The gravity of the room is extremely high, 10 times greater than Earth's gravity. The atmosphere changes dramatically into the deep area of the chamber from extremely cold to extremely hot. The chamber has food resources of a year and has two rest rooms and a bathroom for the users.
Inside the Hyperbolic Time Chamber the time passes slowly comparing to outside. 1 year inside the chamber is 1 day comparing to outside means in inside the visitor will pass a year of equivalent time and in outside it will be only one day of equivalent time. 1 minute of real time is approximately 6 hours in there. The chamber has a big glass of sand which indicates how much time is left to pass a year. There has a clock in the main room which indicates the time of real world. The person who will go inside the chamber cannot pass more than a year in there at a time.
It was mentioned by Piccolo and Mr. Popo that only two person can enter at a time and they can't stay there more than two years (2 days in real time). If someone stays more than 2 years, the entrance will disappear and he will be stack in there and will lost to the dimension forever. In the Majin Buu saga, it was seen that more than two people entered the room - Goten, Trunks, Piccolo and Majin Buu. The number limitations of people was mentioned may be for food resources inside the chamber is only for two peoples for a year.
It is the first time the Z Fighters except Goku trained in Hyperbolic Time Chamber when Cell was on his way to absorb Android 17 and 18. After Goku's cure from the heart disease, he took Vegeta, Future Trunks and Gohan to the Kami's lookout for training to ascend the Super Saiyan level. As the rules of only 2 person can enter at a time, Vegeta and Trunks went first while Goku and Gohan waited outside. Vegeta and Trunks both were ascended here with intense training to take out Cell.
After Vegeta and Trunks's turn Goku entered with his son Gohan. Goku was also ascended here and taught his son to become a Super Saiyan and surpass the level of Ascended Super Saiyan. He succeeded to ascend Super Saiyan level without having bulkier body and sacrificing speed like Trunks did which had massive brute strength but lacked speed. Goku also demonstrated new technique to stay as Super Saiyan in normal lives without the waste of any energy of transformation, by that he could increase his power in more higher level without transformation. In the training process Goku discovered that Gohan had an incredible amount of hidden power which is beyond Ascended form and is known as Super Saiyan 2.
When Vegeta and Trunks couldn't beat Cell in his perfect form for Vegeta's arrogance and proud, they returned to Kami's lookout for further training. Cell gave 10 days of preparation to the Z Fighters to challenge him in The Cell Games tournament. This time Piccolo went first, then Vegeta and then Trunks were last and all of them passed a full day inside the chamber.
When Evil Buu absorbed Good Buu and became Super Buu, he became more arrogant to fight the 2 fighters what Goku was promised to him before the Super Buu transformation. As he had the old memory of Buu, he searched for the two fighters and arrived on Kami's lookout. The two fighters were Goten and Trunks but they weren't ready to fight yet as they were sleeping and the fusion training was also incomplete. Piccolo begged to Buu to spare 30 minutes for the fighters to get prepare. He led Goten and Trunks to the Hyperbolic Time Chamber as every second on outside is 6 minutes inside the chamber and they will get almost 7 days of preparation for 30 minutes of real time. Later the fight took place inside the chamber between the fusion of Goten and Trunks - Gotenks and Super Buu. Gotenks demonstrated Super Saiyan form here but nothing were seemed to enough to stop Buu. As a result Piccolo destroyed the entrance of the chamber to be stack in there forever so that Buu cannot escape. Frustrated Buu shouted horribly and the vibrance of his voice ripped a hole through the dimension and Buu escaped through the hole. Later Gotenks became Super Saiyan 3 inside the chamber to rip a hole like Super Buu did. The combined shout of Gotenks and Piccolo created a similar hole and they escaped through the hole.
In the first episode of Dragon Ball GT : A Devastating Wish - Goku and Uub were training inside the Hyperbolic Time Chamber. It was stated by Goku that Uub were almost or above the level of Frieza during the training. For the intense amount of Energy attacks the chamber became a destructive place which had an impact on Lookout. The whole place was ruined for the intense training. It in unknown how much time they were trained into the chamber.
The list of peoples used the Hyperbolic Time Chamber :
|Location Name||Hyperbolic Time Chamber|
|Romaji Name:||Seishin to Toki no Heya|
|1st manga book:|
|1st anime episode:||Dragon Ball Z #147|
|1st anime movie:|