Fionna the Human Costume
Adventure awaits in this gender-swapped hero look from Ooo.
Fionna the Human is the beloved, gender-swapped version of Finn from Adventure Time. Fans choose this costume for its recognizable, comfortable, and nostalgic design. The look features a blue shirt, denim skirt, thigh-high socks, and her signature white bunny-eared hat.
- Difficulty
- Easy
- Time
- ~20 min
- Budget
- $30–80
Try it on
See yourself as Fionna the Human
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.
Your photo is sent to Google's Gemini API to make the render and isn't used for training. Renders are AI-generated and labelled.
Want a different costume on this photo, or a whole group in costume? Open the Try-On Studio.
What you need for a Fionna the Human costume
Short on time? Buy it ready-made
Spirit Halloween sells the complete Fionna the Human costume — one box instead of 7 pieces.
White bunny-eared hat
A soft, white fleece or knit hat that covers the head and fastens under the chin, featuring two upright bunny ears.
DIY: Sew two stuffed white fleece ears onto a plain white fleece aviator hat or beanie.
Light blue t-shirt
A simple, form-fitting light blue crewneck t-shirt with short sleeves.
Denim mini skirt
A dark blue denim mini skirt, preferably skater or A-line style.
DIY: Cut down an old pair of dark blue jeans into a simple mini skirt.
Thigh-high socks
Solid white thigh-high or over-the-knee socks.
Black Mary Jane shoes
Flat black Mary Jane shoes or simple black ballet flats.
DIY: Use plain black slip-on shoes or flats.
Green backpack
A small, two-tone green round backpack.
DIY: Use a standard green backpack or paint a round canvas bag with light and dark green fabric paint.
Golden sword
A toy sword with a yellow/gold blade and a pink hilt.
DIY: Cut the sword shape out of sturdy cardboard, paint the blade yellow, and wrap the handle in pink tape.
Rather not assemble it? See ready-made Fionna the Human costumes at Spirit Halloween ↗
How to put it together
- 1
Put on the light blue crewneck t-shirt and tuck it neatly into the dark denim mini skirt.
- 2
Pull on the white thigh-high socks, ensuring they sit evenly above the knees.
- 3
Slip into the black Mary Jane shoes or flat black shoes.
- 4
Put on the white bunny-eared hat, fastening it securely under your chin while letting your hair peek out from the sides.
- 5
Strap on the green backpack over both shoulders.
- 6
Grab your golden toy sword to complete the heroic look.
Makeup & hair
Style your hair in long blonde locks (or a blonde wig) flowing out from under the sides of the hat. Keep makeup simple and natural with a touch of pink blush on the cheeks.
Fionna the Human for couples, groups, kids & more
- couples
- Pair up with Cake the Cat, Prince Gumball, or Marshall Lee for a perfect Land of Ooo duo.
- group
- Form a group with Finn, Jake, Princess Bubblegum, and Marceline.
- kids
- A comfortable option for kids using a blue tee, denim skirt or shorts, and a plush bunny hat.
- Plus size
- A stretchy blue tee and an A-line denim skirt offer a comfortable, flattering fit for all body types.
- pet
- Dress your cat as Cake the Cat to accompany you.
Tips
- If your thigh-high socks slide down, use body adhesive or wear skin-toned tights underneath to keep them in place.
- The backpack is fully functional, so use it to carry your phone, wallet, and essentials during events.
- For outdoor events in cooler weather, swap the skirt for blue leggings or skinny jeans.
Fionna the Human costume FAQ
- What color is Fionna's sword?
- Fionna's signature sword has a bright yellow/gold blade, a black guard, and a pink handle with a red gem on the pommel.
- How do you style hair for a Fionna costume?
- Fionna has long, thick blonde hair. If you don't have blonde hair, a long blonde wig works perfectly, with long bangs or sections pulled out to frame the face beneath the hat.
- Is Fionna's hat different from Finn's?
- Yes, Finn's hat has short, rounded bear ears, while Fionna's hat features longer, pointed bunny ears.
Did you know? Fionna first appeared in the season three episode 'Fionna and Cake', which was inspired by character designs created by Adventure Time character designer Natasha Allegri.