Marinette is half-French and half-Chinese. She has light blue eyes, freckles, and black hair with blue highlights that she usually wears back in two pigtails with red bands.
She wears a dark gray overshirt with sleeves and a collar that are white with pink polka dots and outlined with black. Underneath, she wears a white t-shirt with a black collar and sleeve line and a design below the collar with black leaves and pink flowers. Also, she has pink jeans and light pink dress shoes with dark red soles. She wears the earrings, which are silver when not holding Tikki.
As Ladybug, she wears a red suit with a black collar and black spots. Above her hips, she wears her yo-yo around them with the string, and she wears a red mask with black spots. Her earrings become red with five black spots, and the bands holding her hair back become red ribbons. Her hair and her eyes become slightly bluer.
A kind and clumsy girl, Marinette is happy, cheerful, and generous. She loves fashion, her friends and family, and her crush Adrien. But she does struggle with self-confidence and self-esteem. If a situation she deems dangerous, like doing something for Adrien or losing a book that will expose her secret identity, she becomes very nervous and awkward, failing to keep calm and being quick to panic. She deeply cares for other people, and she usually puts their feelings and interests before her own, in some cases being at a personal cost. Despite being genuinely kind, she does have her limits, such as in "The Evillustrator", when she gets irritated with Chloé to the point that, as Ladybug, she refuses to continue watching her to protect her. She can also act impulsively and irrationally at times, as shown when she tries to deflect the false accusation of "stealing" Chloé's bracelet onto others who are also innocent. Although she is absent-minded and acts before thinking at times, mostly if Adrien is involved or she's panicking about a dilemma, she is clever, like hiding her signature in her bowler hat design that exposes Chloé for stealing her design.
As Ladybug, she retains many of the ways she normally acts as Marinette, but she is much stronger and more confident. Her quick-thinking, resourcefulness, and wit comes out a lot more, especially when she is figuring out how to utilize her Lucky Charm. Her superhero job a very serious business to her, she strives to rescue everyone, including the people who became akumatized supervillains. Ladybug, highly aware of how popular and loved she is, is firm in not telling anyone her secret identity, including her partner, Cat Noir, in fear of dissatisfying everyone with her plain, less amazing alter ego. No matter how hard the tasks before her are, she will do everything in her power to set things right and bring peace back to those in trouble.
Marinette knows how to be a fashion designer. She sketches ideas in a notebook, and she can sew by hand or with a machine. Her skills in this field are exceptional for an amateur, such as when it was shown that the bowler hat she made is good enough to be recognized by a professional designer, Gabriel, despite the fact that she has never made one before. Marinette also appears to have high stamina and endurance even in her civilian form, as she was seen running long distances without stopping in several episodes.
As Ladybug, she has enhanced skills, such as speed, agility, strength, and observation. She has remarkable talent with wielding her yo-yo, like using it as a grappling hook, rope, and attack. Her special power, Lucky Charm, helps her by summoning an object that'll help her achieve her objective, it often being to stop a villain. However, it drains her power and reverts her back to Marinette shortly afterwards, so she has to use it wisely. After the akuma is released from its corrupted object, she can open her yo-yo and throw it to grab it, remove the energy that Hawk Moth charged it with, and release it as a normal butterfly. Once the akuma is dealt with, Ladybug can throw her Lucky Charm object into the air, which will make it revert back to energy and fix all of the damage done since the villain was created.