Anna is depicted as a carefree, passionate, and heartwarming person, who believes in the best of people even when they're at their worst, particularly Elsa. Years of isolation from the world and her sister has left Anna lonely, but her pure heart kept her strong. She is also selfless, as she willingly sacrificed herself to protect Elsa.
Anna is slightly shorter than her sister, Elsa. She has blue eyes, freckles on her face, and wears her strawberry blond hair in braid pigtails. She initially had a long streak of platinum blond hair, which she wears on her right braid: a direct result of getting hit on the head by Elsa's magic as a child, but it disappeared after Anna's act of true love removed all the ice magic from her body.
Anna first encounters Sora, Donald Duck and Goofy while traversing up the North Mountain with Sven, Kristoff, and Olaf for company in search for her sister, Elsa, who had run away from the kingdom after she accidentally unleashed her ice magic and turned summer into winter. When she tells Sora that Elsa is her sister, he tells her that Elsa is in trouble. Anna then tells them what happened at the coronation party. Kristoff, Sven, and Olaf ran into some Heartless, and Olaf fell apart from the attack. After Sora and co reassembled his body, the Heartless return, forcing Anna and her friends to leave the trio to deal with the monsters.
Upon reaching the Ice Palace, Anna tells Elsa what her magic had caused, but is confident that she can undo it. When Elsa screams with distraught, her magic accidentally strikes Anna's heart, then she creates Marshmallow to send her sister away. Anna angrily throws a snowball at the snow monster, angering him. Sora and the others catch up and lead the monster astray while Anna and Kristoff escape. Having been struck by Elsa's magic and beginning to freeze, Kristoff takes her back to the kingdom where she could receive true love's kiss from her boyfriend, Hans.
Later, as a storm descends upon Arendelle, Anna escapes the castle with the cursing about to freeze her completely and finds Kristoff, who wishes to save her with his love for her. She spots Hans about to take down her sister, and chooses to save her instead of herself. Her body transforms into an ice statue right before Hans's sword hit her and the impact knocks him unconscious. Sora, Donald, Goofy, Olaf, Sven, and Kristoff arrive to witness her selfless act before the darkness within Hans sent the trio into a dark abyss to fight a powerful Heartless. After defeating it, Anna unfreezes, and Larxene surmises that not only is Elsa one of the new seven Princesses of Heart, but Anna is as well. She then tells them the Organization will go after them if Sora's group fails to gather all Seven Guardians of Light. Sora barks that their group is one member short, but Larxene tells him "we're set" before taking off. Sora then worries that Elsa and Anna will be in trouble if they don't find all seven, but Goofy tells him they have each other. Anna inspires Elsa to find the way to reverse the magic and the eternal winter is lifted.
Anna is last seen sleighing down the mountain with Kristoff and Sven; Elsa creatures an ice bridge to catch them.
Anna is one of the main characters in the 2013 Disney animated film, Frozen.