- Matey - A puppy found when he tried to jump onto a boat but missed and was saved by Ariel.
- Seashell - A pony met by Ariel and was turned into a real horse by King Triton.
- Treasure - A kitten found on Prince Eric's ship.
- Sandy Pearl - A baby seal.
- Otto - A sea otter found Singing with Ariel.
- Waddles - A puffin.
Ariel was originally a mermaid who longed to see more of the human world, other than the various items and trinkets that would fall into the sea. After she met Prince Eric she was soon transformed into a human, where she remains to this day. She has two best friends who come from the sea, Flounder the fish, and Sebastian the crab.
Ariel is a fair-skinned girl with bright blue eyes and bright red, slightly curled hair. She has pink lips and wears a silver tiara with blue accents. She wears a glittering, cyan semi-pleat dress with pale mint frilly petticoat beneath it. Around her waist is a very pale glittering skirt layer to match the sleeves worn over each arm. She wears shell earrings to match the accessory sewn to the center of her chest.
When she was younger, Ariel had less curled hair. She was shown in a short pale green and sky blue dress with white frilly tulle around the waist and sleeves. Bows accent the center of the skirt, while a purple flower was sewn to the middle of the tulle layer. She wore matching flats with a single bow on each toe. Her crown matches the tiara her older form wears.
Ariel is a bright and spirited young girl full of curiosity. She is adventurous but stubborn, and this sometimes gets her into trouble or gets the better of her. While impulsive, she tries not to let it block her judgement and she is shown to hesitate or get extremely reluctant if at any time she knows something may be morally wrong.
To reach her goals and dreams, Ariel has no problem choosing to risk everything in order to get it. Even if it may hurt her in the end or cause problems. She is highly protective over those she cares about and has no problem risking her own safety; with her energetic and courageous personality she will never shy away from an obstacle. Her bravery and kindness for others makes her very forgiving. She tries to remain hopeful, even when her belief is shaken or questioned.
Like her father, Ariel has been shown to have a bad temper when provoked. She also has some self-doubt in herself, and at one point wondered if she truly had been a freak for having any fascination for humanity. While everyone else seemed to fear it, she questioned it and longed to know more. Despite her usual naivety and impulsiveness, Ariel has shown on many occasions to be serious, careful, and very intelligent and intuitive.
As she grows, she has shown to mature. This is best seen in The Little Mermaid II: Return to the Sea, when she has become a mother. Due to the threat of Morgana, she becomes very overprotective of Melody in the same manner she was treated by Triton in the first film. She is shown to long for the sea, but keeps this hidden from Melody for the latter's own safety; even though it would've been easier if she had explained everything to her, and points this out eventually.
While she is a Mermaid, Ariel has a few abilities.
- Atlantean Strength: She is known to have at least a very certain degree of Atlantean strength, as she was able to move away from an underwater boulder blocking her grotto with relative ease in the original film. When discovering Eric's ship due to the fireworks, she is shown effortlessly climbing up the side of the ship with just her arms. When saving him, she effortlessly pulls him towards the surface and manages to keep them both afloat while holding him with one arm. In Ariel's Beginning, she seemed to be able to break the lock on a door to free her friends (albeit using a rock, but this is still especially telling as Sebastian stated immediately prior that she was "a weak helpless girl"). It's debatable if she ever retained her Atlantean strength by the time she became a human.
- Atlantean Endurance: Ariel may also have Atlantean endurance, as, during the final battle with Ursula in the film, she was at one point knocked into a whirlpool that is several miles deep and survived with barely any injuries. Such a feat would kill a normal person if not completely destroy the body of a said person. Like her Atlantean strength, it's debatable if she ever retained her Atlantean endurance when she turned into a human, although her first transformation implied that it was retained as her body was not being crushed while trying to swim for air.
- Underwater Breathing: As a mermaid, Ariel is also able to metabolize oxygen from the water, which negates the need to surface, though she is certainly more than capable of breathing on land.
- Speed Swimming: Also, Ariel is capable of swimming at a much faster rate than humans or even certain marine creatures in terms of undersea travel, or sea travel as a whole due to her half-marine status. Like dolphins, she is capable of leaping out of water at great heights. For example, she was able to get to King Triton's palace from Prince Eric's kingdom in less than a day, as well as getting from Atlantica to Norway in the episode "Metal Fish" in a similar time fashion.
- Aquapathy: Because of her being a mermaid, Ariel is also capable of speaking with aquatic fauna. She retains her ability even in human form.
- Swordswoman: While in human form, Ariel seems to at least have gain some knowledge of swordplay, which is evident when she used one to cut the rope off a mast to save Melody from Morgana.
- Rapid Adaptability: Ariel also seems to be capable of rapid adaptability. This is especially evident in terms of her becoming a temporary human, where she learned how to stand in a few minutes, and move in presumably the same timespan, as well as quickly learning about the true human customs and abandoning her original beliefs about how human artifacts work, or at the very least not doing it in public.
- Thermoendurance: Ariel has demonstrated the ability to endure temperatures far more extreme than would be survivable for a human (especially one of her build). This is shown in the films and TV series, where she went to the arctic with minimal ill effects other than feeling a bit cold, as well as in Return to the Sea, where she traveled to Morgana's lair, which was located inside an iceberg, and when visiting Ursula's, which was located in a volcanic region.
- Magical Voice: Ariel's voice seems to possess magical abilities. In the episode "The Evil Manta" of the TV series, her singing voice seemed to be the only weapon that could banish the Manta from Atlantica. Her voice conjured an underwater storm that cast the Manta out of the empire. In another episode of the TV series known as "Giggles", she was cursed that if she laughed her laughter would cause Sea-Quakes; however, this curse was removed by the end of the episode. Her voice was also able to awaken an unconscious Eric. Although she herself never used her voice in this manner, her voice can also be used in a far darker way, such as mind control, as evidenced by Ursula, while adopting the identity of Vanessa, using Ariel's voice to brainwash Prince Eric to be her puppet as a means to get him to marry her, and thus ensure Ariel can't win her end of the bargain. This ability can be further proven for the only way Vanessa's (Ursula's) control over him could be broken was if the nautilus containing Ariel's voice was released.