Adventure Time Costume
Mathematical! Journey to the Land of Ooo as Finn the Human.
Adventure Time is a beloved animated series known for its whimsical characters, surreal humor, and deep lore. Dressing up as Finn the Human is a popular choice for fans of all ages because his look is instantly recognizable and highly comfortable. This guide focuses on Finn's classic outfit, featuring his signature white bear-eared hat, blue tee, and green backpack.
- Difficulty
- Easy
- Time
- ~20 min
- Budget
- $25–65
Try it on
See yourself as Adventure Time
One clear photo of yourself; we render you in this costume — face untouched, full body, about 20 seconds.
One render, $1. No account needed — if it fails you're not charged. Pricing.
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Want a different costume on this photo, or a whole group in costume? Open the Try-On Studio.
What you need for a Adventure Time costume
Short on time? Buy it ready-made
Spirit Halloween sells the complete Adventure Time costume — one box instead of 7 pieces.
White bear-eared hat
A white fleece hood or beanie with two distinct rounded ears on top that fastens under the chin.
DIY: Cut the hood off an old white hoodie and sew two stuffed white fleece ears to the top.
Light blue t-shirt
A simple, solid light blue crewneck cotton t-shirt.
Dark blue shorts
Solid dark blue or navy athletic shorts that sit above the knee.
DIY: Cut old blue jeans or navy sweatpants into shorts.
Two-tone green backpack
A round canvas backpack featuring a light green body and a dark green circular front pocket.
DIY: Take a plain green backpack and fabric-paint the front pocket a darker shade of green.
White crew socks
Classic white athletic crew socks rolled down slightly to the ankles.
Black slip-on shoes
Simple black canvas slip-on shoes or low-top sneakers.
Golden sword
A toy golden sword with a blue circular gem in the hilt, representing Scarlet the Golden Sword.
DIY: Cut the sword shape out of sturdy cardboard, paint the blade gold, the hilt black, and add a blue paper gem.
Rather not assemble it? See ready-made Adventure Time costumes at Spirit Halloween ↗
How to put it together
- 1
Put on the light blue crewneck t-shirt and dark blue shorts.
- 2
Pull on the white crew socks and roll them down slightly so they sit just above your ankles.
- 3
Slip into the black canvas shoes.
- 4
Secure the white bear-eared hat over your head, fastening it under your chin if it has straps, ensuring your hair is fully tucked inside.
- 5
Put on the two-tone green backpack over both shoulders.
- 6
Carry the golden toy sword in your hand or tuck it securely into the side of your backpack strap.
Makeup & hair
No makeup is needed. Finn's hair is completely hidden beneath his white hat, but if you take it off, you can wear a long, flowing blonde wig to represent his beautiful golden locks.
Adventure Time for couples, groups, kids & more
- couples
- Pair Finn with Jake the Dog (using a yellow morph suit or hoodie) or Princess Bubblegum (in a pink gown with a gold crown).
- group
- Add Marceline the Vampire Queen, Ice King, and BMO for an awesome Land of Ooo group ensemble.
- kids
- This is an incredibly easy and comfortable costume for kids, requiring just a blue tee, shorts, and the signature fleece hat.
- Plus size
- The loose-fitting t-shirt and elastic-waist athletic shorts offer a highly comfortable, flexible, and true-to-character fit for all body types.
- pet
- Dress your dog in a simple yellow knit sweater or hoodie to transform them into Jake the Dog.
Tips
- Keep your hair completely tucked into the hat to maintain Finn's classic animated silhouette.
- The backpack isn't just a prop—use it to carry your wallet, keys, phone, and convention snacks.
- If you are attending an event with strict weapon policies, opt for a soft foam or cardboard DIY sword instead of hard plastic.
Adventure Time costume FAQ
- What kind of hat does Finn wear?
- Finn wears a white fleece hood with two rounded bear-like ears that covers his entire head and fastens under his chin.
- How can I make Finn's green backpack?
- You can use a standard light green backpack and use dark green fabric paint or a sewn-on felt circle to create the darker green front pocket.
- What color is Finn's sword?
- Finn's classic sword, Scarlet, is gold with a silver-edged blade, a black hilt, and a small blue gem at the bottom of the handle.
Did you know? Finn's iconic white hat was inspired by a comic strip character named 'Bueno the Bear' created by Adventure Time's creator, Pendleton Ward.