Finn the Human Costume
Mathematical! Suit up as Ooo's greatest hero with this easy guide.
Finn the Human from Adventure Time is a beloved cosplay choice for fans of all ages who want a fun, recognizable, and highly comfortable outfit. His signature look consists of simple blue garments, a distinctive two-eared white hat, and his trusty green backpack. It is an incredibly easy costume to put together using everyday clothing items and a few key accessories.
- Difficulty
- Easy
- Time
- ~15 min
- Budget
- $25–60
Try it on
See yourself as Finn the Human
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What you need for a Finn the Human costume
Short on time? Buy it ready-made
Spirit Halloween sells the complete Finn the Human costume — one box instead of 7 pieces.
White Finn Hat
A white fleece or plush hood that covers the head and ears, featuring two small rounded bumps or 'ears' on top and a chin strap closure.
DIY: Cut and sew a basic hood shape from white fleece fabric, stuffing two small fabric triangles at the top with cotton balls.
Light Blue T-Shirt
A plain, short-sleeved crewneck t-shirt in a solid light blue or sky blue color.
Dark Blue Shorts
Simple, comfortable dark blue or royal blue shorts that sit above the knee.
Green Backpack
A two-tone green backpack, ideally with a lighter green body and a darker green circular front pocket.
DIY: Take a standard green backpack and fabric-glue a dark green felt circle to the center pocket.
White Socks
Classic white crew socks rolled down slightly to sit just above the ankle.
Black Shoes
Simple black slip-on shoes, sneakers, or Mary Janes.
Toy Gold Sword
A toy sword with a gold blade, a silver hilt, and a red gem detail on the pommel.
DIY: Cut a sword shape out of sturdy cardboard, paint the blade gold, the guard silver, and add a red plastic gem to the hilt.
Rather not assemble it? See ready-made Finn the Human costumes at Spirit Halloween ↗
How to put it together
- 1
Put on the light blue short-sleeved t-shirt.
- 2
Put on the dark blue shorts.
- 3
Pull on the white crew socks and roll them down slightly so they bunch around your ankles.
- 4
Slip on the plain black shoes.
- 5
Secure the white fleece Finn hat over your head, fastening the chin strap if it has one, making sure your hair is tucked inside.
- 6
Put on the green backpack, adjusting the shoulder straps so it sits comfortably on your back.
- 7
Carry your toy gold sword in your hand or tuck it securely into the side of your backpack strap.
Makeup & hair
No makeup is required, and all hair should be completely tucked away inside the white fleece hat to mimic Finn's hidden golden locks.
Finn the Human for couples, groups, kids & more
- couples
- Pair up with Jake the Dog, Princess Bubblegum, or Marceline the Vampire Queen.
- group
- Assemble a full Adventure Time group with Finn, Jake, Ice King, Princess Bubblegum, and BMO.
- kids
- An excellent, comfortable choice for kids using a blue t-shirt, shorts, and a cozy plush hat.
- Plus size
- The loose-fitting t-shirt and elastic-waist athletic shorts offer a highly comfortable, flexible fit for all body types.
- pet
- Dress your dog in a yellow pug-style sweater or hood to be your real-life Jake the Dog.
Tips
- The backpack isn't just for show—use it to carry your wallet, phone, keys, and snacks while trick-or-treating or walking a convention floor.
- If you want a fun reveal, wear a long blonde wig underneath the hat and dramatically pull the hat off to show your 'beautiful golden hair' just like in the show.
- Keep the clothing simple; avoid shirts with visible modern brand logos to keep the cartoon aesthetic clean.
Finn the Human costume FAQ
- What kind of hat does Finn the Human wear?
- Finn wears a white, form-fitting fleece hood with two small rounded ears on top, which is modeled after a bear's head.
- What color is Finn's backpack?
- Finn's backpack is two-tone green, featuring a light green main body and a darker forest green circular front pocket.
- Is Finn the Human an easy DIY costume?
- Yes, it is one of the easiest DIY costumes because it relies on a basic light blue t-shirt, dark blue shorts, white socks, and black shoes, requiring you to only buy or make the hat and backpack.
Did you know? Finn's iconic white hat was inspired by a comic strip creator Pendleton Ward drew called 'Bueno the Bear' before creating Adventure Time.