|Age||6 or 5|
|Family||Milli (Sister), Bot (Guardian), Umi-Car|
|Abilities||Super Shape Power|
|First Appearance||The Big Boat Race (chronologically), The Kite Festival (airing order)|
|Voiced By||Ethan Kempner (Seasons 1-3), Juan Mirt (Season 4)|
Geo is Milli's brother, and also the deutertagonist of Team Umizoomi, voiced by Ethan Kempner from Seasons 1-3 and by Juan Mirt in Season 4.
Geo has blue hair. He usually wears a blue shirt, blue pants, blue/orange skates, and a blue helmet. He wears an orange square belt known as the Shape Belt with a triangle, square and circle (in order) on each side of the belt. His dimple smile is hard to miss.
In Movie Madness!, he wears black sunglasses, when the team was in the spy movie.
- Super Shapes: The main power of Geo. It mostly consists building items out of shapes.
- Shape Splitter: A sword that could split any shapes to build the item. This power was introduced in "DoorMouse in Space", and was also used in "The Kitty Rescue" and "Animal School House."
- Shape Magnet: A power introduced in the Season 3 episode "Rainy Day Rescue". Also used in other episodes such as "The Umi City Treasure Hunt" and "City of Lost Penguins". Geo holds a magnet which can attach to or attract any kind of shape.
- Antennae: The antennae on Geo's helmet are not just for decoration. He uses them to make blue prints. He slightly tilts his head to the right and the antennae make the blue to look like whatever he wants it to look like. In Team Umizoomi VS. The Shape Bandit, he made blueprints that were made up of objects he found around the area. In Movie Madness!, while in the spy movie, he used the sunglasses he was wearing to make a blueprint.
Geo tends to shows his feelings more than the other members of the team, and he's also a bit sensitive. Aside from that, he has a very sparky personality and a "GO!GO!GO!" approach to life. Since he has so much ambition in him, Geo never gives up until the end and always tries his best. He also has a bit of a prankster side revealed in "Doctor Bot" when he hid a toy chicken on himself to trick Bot when he was checking his heartbeat. He is also the fastest member of the team.
You can never find Geo not wearing his Super Skates; he love roller-skating more than anything else, except his friends. In The Aquarium Fix-It, he is revealed to have a pet sea horse named Finn. In Cuckoo Bears, it is revealed that Geo has some experience in playing the bass. His favorite food is pepperoni pizza.
All we know is is that Geo was born after Milli. It's unknown whether he or someone else created the Shape Belt.
- "Geo" is a prefix meaning Earth. It also relates to Geometry.
- In "Team Umizoomi vs. The Shape Bandit" even without his shape belt, he still has his powers and make anything with shapes found in his surrounding.
- Geo has been known to express his emotions more than the other members of Team Umizoomi. He has an excited scream, an angry face, and his ambitious face.
- In certain episodes, Geo shows negative feelings against DoorMouse . We currently don't know why he does.
- As of DoorMouse in Space, Geo has been the first member of Team Umizoomi to show his teeth.
- "Hold on to your helmets!"
- "We got you, buddy!" (often to Bot)
- "Sea-horse power!" (from "The Aquarium Fix-It")