最初被認為是家庭成員 中唯一沒有超能力。小傑在電影結尾時展現出多種超人的能力，其中大部分都是變形的類型。在短片《小傑的攻擊》中可以看到更多的超能力， 使他成為家中最多才多藝的人，並根據一些《超人特攻隊》玩具中所包含的收藏海報，似乎小傑仍然有更多超能力並未公開。 在超人特攻隊2中，他的家人發現他至少有17種超能力。
Jack-Jack is small, albeit at the average size for a baby as he stands 2'6". He is handsome and slender and has a single tuft of light brown hair on his head. Although he is usually seen in a yellow onesie during his on-screen appearances in the film, he is usually remembered for wearing a red supersuit with a black mask.
When he transforms into a little monster, Jack-Jack's skin turns red and gains sharp fangs and claws, that he can use to defend himself and look intimidating.
Mozart's music will trigger Jack-Jack into manifesting his powers, which Edna Mode uses to design a new suit that has sensors and a hand-held monitor, which alerts his family to upcoming use of his powers and allows them to counter them quickly. His powers and abilities are significant enough for his siblings to use him as a third member of a rescue team.
- 改變外形: 他可以模仿他人的外形特徵，例如鼻子和頭髮，不確定這部分是否只能改變自己。
- 怪物型態: 被激怒時會變成紅色的怪物外貌，會抓和咬激怒他的事物。
- 控制火: 當小傑在身上產生火時，他可以使火焰籠罩一個區域，在遊戲 樂高超人特攻隊中還可以發射火雷射。
- 瞬間移動: 可以消失並神秘地出現在幾公尺之內的地方。
- 穿透: 可以透過硬的東西。
- 爬牆: 可以黏、爬、坐在天花板或垂直的牆上。
- 強放咬/物質吸入: 他可以吃或咬物品。
- 念力: 小傑可以用心智來移動物體。
- 飄浮: 他可以將自己昇到空中。可以控制要要去的方向、高度等。
- 雷射眼: 他可以從眼睛發出綠色的雷射 (在《小傑的攻擊》中是藍色) 該雷射可以由鏡子反射。
- 力量強化/Impervious Skin: 力量可以與浣熊對抗，而且不受傷害。
- 次元旅行: 他能穿過次元的邊界（被衣夫人標記為4）被穿梭旅行。他可以透過次元聽到或被聽到。
Jack-Jack is first introduced being bathed in the sink by his mother, 荷莉 as she talks on the phone to his father, 鮑伯. He is later seen at dinner, with Helen trying to get him to eat his baby food by making funny faces, which he mimics. This also makes his older brother, Dash, feel weird. He laughs when his older siblings, 小倩 and 小飛, get into a fight, enjoying the action and thinking they are playing.
In the montage scene, Jack-Jack seen being taken care of by Bob, who has recently gained a large amount of confidence, after secretly taking a job on a remote island. He gives him a kiss on the cheek. Realizing that his dad has come to care for him more despite the latter's responsibilities, Jack-Jack giggles. Helen encourages Bob to take a turn feeding Jack-Jack, which he does. Later, Dash and Violet stow aboard a plane Helen had rented, and quickly called Violet's friend, Kari McKeen, to babysit him. The baby is seen playing with an orange ball in his high chair while 麥凱莉 is talking to Helen on the phone.
He is not seen again until the end of the movie when Syndrome tries to kidnap him to raise him as a sidekick to get revenge on his family. However, thanks to Kari playing Mozart for him, he has learned of his powers and uses them (fire, steel, and demon forms) to escape from Syndrome who is flying up towards his hoverjet. As he is falling towards the ground, Helen catches him. He and the rest of the family are then saved from Syndrome's exploding plane thanks to Violet's force field. Jack Jack then joins the others in laughter after Dash asks if they will have to move again. At the end of the movie, he is shown clapping for Dash from the bleachers during the track meet and is then shown to be ready to fight 採礦大師, thereby setting up the events of the sequel.
In his own mini-movie, we see what happens to him and Kari while the rest of the family is fighting Syndrome. Kari decides to stimulate his cognitive abilities by giving him some educational toys and playing Mozart for him (as she has heard that Mozart makes babies smarter). Listening to the music, he has an epiphany about his powers.
Over the course of the night, he demonstrates many different powers, such as floating through the walls, catching on fire, and shooting laser beams out of his eyes, and Kari tries to keep him and the house in one piece. By morning, Kari has been up all night and figured out how to counter his powers. In her frazzled state of mind, she hands him over to Syndrome, whom she believes to be a replacement babysitter contacted by Helen.
- According to official sources, Jack-Jack is 1 year old, is 2'4" (0.71 m) and weighs 30 lbs (13 kg).
- Jack-Jack is not seen or mentioned in the video game and is the only non-playable character of the Parr family in the 迪士尼無限世界系列 (he does, however, appear in early concept art for the game, indicating he was likely to appear as an NPC as part of the Incredibles playset before being dropped and is mentioned directly by Helen in her in-game quotes when she is left idle, wondering how Kari is handling him).
- In the comic series, Jack-Jack is a main character but his only used power is that of molecular transformation and appears limited to metal, fire, and monster forms. In the story arc "City of Incredibles", he plays a central role when he gets a cold and inadvertently spreads his transformation powers to others (including his own family), causing their own natural superpowers to be updated to their maximum potential.
- On art and merchandise, Jack-Jack wears his super suit, but in the first film itself, he doesn't at all (except for the very end of the film).
- Jack-Jack has 17 known superpowers, potentially making him the most powerful Super in the Incredibles universe.
- However, he could have just general shape-shifting powers.
- It was planned for Jack-Jack to melt as part of his shape-shifting powers, but this idea wasn't used; it can be assumed that this was due to technical limitations at the time or the fact that it would have seemed too disturbing for younger viewers at the time.
- This limitation appears to have been corrected for the 2018 sequel as seen during his fight against the raccoon.