What breed of dog is Underdog?

Underdog is a heroic anthropomorphic beagle, which is why floppy brown dog ears are a key part of the costume.

How do I make a quick DIY Underdog costume for my dog?

Find a red dog shirt or a child's red t-shirt, fabric-glue a white felt letter 'U' to the back, and tie a small strip of blue fabric around their collar as a cape.

What are Underdog's main costume colors?

The classic color scheme is a bright red top and bottom, a royal blue cape, a white letter 'U' on the chest, and brown floppy ears.

Underdog halloween costume for dogs

The ultimate Underdog look: dress your dog (especially a beagle) in a custom red dog t-shirt with a white 'U' and a lightweight blue cape.

Underdog

Underdog Costume

There's no need to fear, Underdog is here!

Underdog is the beloved anthropomorphic canine superhero from the classic 1960s animated series. This costume is a nostalgic favorite for cartoon fans, characterized by a bright red outfit, a blue cape, and a bold white 'U' on the chest. Whether you are dressing up yourself or styling your favorite pup, this look is instantly recognizable and fun.

Difficulty: Easy
Time: ~30 min
Budget: $20–50

See yourself as Underdog →What you need Buy the Underdog costume

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See yourself as Underdog

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One render, $1. No account needed — if it fails you're not charged. Pricing.

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You as Underdog

Result

What you need for a Underdog costume

Short on time? Buy it ready-made

Spirit Halloween sells the complete Underdog costume — one box instead of 5 pieces.

Shop Underdog at Spirit ↗

Red long-sleeve shirt
A solid, bright red crewneck sweatshirt or long-sleeve t-shirt.
DIY: Use a plain red t-shirt you already own.
Amazon
White felt 'U' patch
A large, bold capital letter 'U' cut from white felt or fabric.
DIY: Cut a large letter 'U' out of white felt or paper and safety pin or fabric glue it to the chest of the red shirt.
Amazon
Red pants
Solid red sweatpants, leggings, or trousers to match the shirt.
DIY: Use red jeans or red leggings.
Amazon
Blue cape
A simple, lightweight royal blue cape that ties around the neck.
DIY: Cut a piece of royal blue fabric or a blue t-shirt and safety pin it to the shoulders of the red shirt.
Amazon
Dog ears headband
A headband featuring long, floppy brown dog ears to capture the beagle look.
DIY: Cut long ear shapes out of brown felt and glue them to a plain black headband.
Amazon

Rather not assemble it? See ready-made Underdog costumes at Spirit Halloween ↗

How to put it together

1
Put on the solid red pants or leggings.
2
Prepare the red shirt by centering the large white 'U' on the chest and securing it with fabric glue, iron-on adhesive, or safety pins.
3
Put on the red shirt with the 'U' facing forward.
4
Fasten the royal blue cape around your neck or pin it securely to the shoulders of the shirt.
5
Place the brown floppy dog ears headband on your head.
6
Complete the look with simple black or white sneakers.

Makeup & hair

Keep hair simple or tucked under the headband. For a fun touch, use black face paint or an eyeliner pencil to draw a small black dog nose on the tip of your nose.

Underdog for couples, groups, kids & more

couples: Pair up with Sweet Polly Purebred wearing a yellow dress and a blonde wig.
group: Add Simon Bar Sinister in a black trench coat and top hat, and Riff Raff in a gangster suit.
kids: An adorable option using a red toddler onesie with a felt 'U' and a small blue cape.
Plus size: Use a loose-fit red crewneck sweatshirt and matching red sweatpants for a comfortable, size-inclusive fit.
pet: The ultimate Underdog look: dress your dog (especially a beagle) in a custom red dog t-shirt with a white 'U' and a lightweight blue cape.

More ways people search for this costume

The most-searched variations of “Underdog costume”, and how this look adapts to each.

Underdog halloween costume for dogs: The ultimate Underdog look: dress your dog (especially a beagle) in a custom red dog t-shirt with a white 'U' and a lightweight blue cape.

Tips

Ensure the shade of red for the top and bottom matches as closely as possible for a cohesive uniform look.
If dressing up your pet, make sure the cape is lightweight and doesn't drag on the ground to keep them safe and comfortable.
Use safety pins to secure the cape to the shirt shoulders so it doesn't pull uncomfortably on your neck during the night.

Underdog costume FAQ

What breed of dog is Underdog?: Underdog is a heroic anthropomorphic beagle, which is why floppy brown dog ears are a key part of the costume.
How do I make a quick DIY Underdog costume for my dog?: Find a red dog shirt or a child's red t-shirt, fabric-glue a white felt letter 'U' to the back, and tie a small strip of blue fabric around their collar as a cape.
What are Underdog's main costume colors?: The classic color scheme is a bright red top and bottom, a royal blue cape, a white letter 'U' on the chest, and brown floppy ears.

Did you know? Underdog's alter ego is Shoeshine Boy, and he famously speaks in rhyming couplets, most notably declaring, 'There's no need to fear, Underdog is here!'