Kristoff is a fictional character in Walt Disney Animation Studios' Frozen franchise. He appears in the animated features Frozen (2013) and Frozen 2 (2019), and the animated short films Frozen Fever (2015), Olaf's Frozen Adventure (2017) and Once Upon a Snowman (2020). Kristoff is one of two leading men in Frozen who take the role of Anna's love interest. His soft-hearted character was designed to contrast with the calculating personality of Hans. Kristoff and Anna's relationship develops out of friendship and was intended to depict the reality of love, as opposed to the hasty, romantic nature of Anna's engagement to Hans.

Kristoff was created by co-directors Chris Buck and Jennifer Lee and is voiced primarily by Jonathan Groff. He is a rugged iceman who lives in the mountains with his reindeer companion Sven. His design takes inspiration from traditional Sámi culture. Quiet and reclusive, Kristoff prefers a solitary life, but after meeting Princess Anna of Arendelle, he helps her on her journey to find her older sister Elsa on the North Mountain after she freezes summer with her powers.

Kristoff has received a positive reception for his sensitive and supportive character and his healthy approach to relationships. Critics have praised him for subverting the role of the traditional Disney prince and for representing a shift in Disney's portrayal of masculinity and gender roles, making him a positive role model for children.

Development Origins and conception Frozen is loosely based on "The Snow Queen", a fairy tale written by Hans Christian Andersen. Walt Disney Animation Studios made several attempts to adapt the original story to film. In 1943, Walt Disney collaborated on a live-action biopic of Hans Christian Andersen and some animated versions of his stories with Samuel Goldwyn. After parting ways with Disney, Goldwyn went on to produce the film Hans Christian Andersen (1952). As a result, various unfinished projects at Disney, including The Snow Queen and The Little Mermaid, were abandoned. Disney returned to the story in the late 1990s. Chris Buck, who had previously co-directed Tarzan, pitched one of the story concepts titled Anna And The Snow Queen, but it was not until after the release of Tangled (2010) that the film was reimagined with a completely different story concept and with Buck as director. Buck said that his early inspiration for the story aimed to "do something different on the definition of true love. Disney had already done the 'kissed by a prince' thing, so thought it was time for something new". Producer Peter Del Vecho said that The Snow Queen is "a pretty dark tale and it doesn't translate easily into a film", thus the final film departs heavily from the original. He joined the project in 2011, while it was in development. Jennifer Lee was brought in as a writer but she had such passion for the project that she became co-director alongside Buck to save time by sharing duties. The story planning involved Del Vecho, Buck, Lee, the head of story and the songwriters working together.

The story of Frozen underwent numerous revisions and was initially much different from the final plot. Anna was originally intended to be a kind heroine, while Elsa was supposed to be the antagonist, akin to the character in the Hans Christian Andersen tale. Elsa has assembled an army of snow monsters in the final act, resulting in Kristoff coming to Anna's rescue. Del Vecho said that the story concept had to be changed because it felt like it had been done before and the characters were not relatable. Buck helped to develop the moment when Anna's heart is frozen by questioning "Does it always need to be true love's kiss that solves that problem? Does it always have to be the man who comes in and rescues the female?" The team eventually realised that the solution was an act of selfless love by Anna. Lee produced a new script for the final act but they were having a hard time staging it until a story artist named John Ripa storyboarded the solution with Elsa's emotions producing a blizzard. By showing Kristoff in the blizzard just before Anna and Elsa arrive, this gave the plot twists the perfect amount of time to develop and give viewers the impression that he will offer the answer.

During development, the filmmakers conducted research on relationships between brothers and sisters. For Kristoff, the Frozen team surveyed men about what it is like to have relationships with strong women. Lee stated "we were trying to get at what it's like to be a guy, trying to understand women". Kristoff continually changed throughout development and, in an early draft, he was written as a hoarder. Songwriters Robert Lopez and Kristen Anderson-Lopez originally wrote a full song for him instead of the short lullaby that appears in the final film. In early drafts of the film, Anna flirted with Kristoff immediately upon their first meeting, but this was changed after Walt Disney Studios chairman Alan Horn said that it would be confusing.

Voice

Kristoff is primarily voiced by Jonathan Groff, while he is voiced as a child by Tyree Brown. Groff's casting was officially announced by Walt Disney Animation Studios in December 2012. Groff said that he was cast after Idina Menzel and Kristen Bell, with much of the casting process focusing on whether his voice was the right fit for Kristoff. During his audition, he recorded a few scenes and sang a Stephen Sondheim song "Everybody Says Don't" from Anyone Can Whistle, as Disney was searching for a voice that would work well with Bell's. Lee reacted to his voice, saying "everyone was swooning" because it was "like butter". Kristoff was Groff's first voice work in an animated feature and he was surprised to discover that the process involved recording the dialogue alone in a booth rather than working with the other actors. The role required him to record dialogue every six weeks for a year and a half. While recording his voice, the animators took video recordings of Groff and incorporated his facial expressions into the character's animation.

Characterisation Kristoff is an ice harvester with a tough, rugged and scruffy appearance. He has a quiet demeanour and few friends apart from his reindeer Sven. Animator Tony Smeed said, "He doesn't relate to humans as much as he does animals." He worked on Kristoff to convey his thoughts and emotions using very few words and felt that his understated character meant that he would need to use just enough of his strength to complete the job. Paul Briggs, head of story, said that he represents the "code of being a man" by having a tough exterior but being soft at heart. He explained that he wears a mask that hides his true self and that Anna helps him to lower it. Lee confirmed that Kristoff is an orphan at the beginning of Frozen. Due to his love of the outdoors, he comes across Sven and befriends him. Groff said that as a result of Kristoff being raised by trolls and living in the wilderness, he does not have social graces and finds it difficult to communicate with others. He commented, "He's sort of charming but he doesn't realise that he's charming" because he has spent a lot of time living alone. Kristoff's story arc begins with him being a loner and the events force him to integrate back into society, which changes him as a person.

When discussing the two leading males in Frozen, Buck said that he and Lee wanted to create flawed characters. Lee said that their aim was to make Kristoff and the other characters "relatable and genuine". Del Vecho said that the characters respond differently in the same situations just like in real life, thus Kristoff is rugged, practical and lives "day to day", while Hans lives a more privileged, calculated life. Buck said that Kristoff represents "the messy part" of real love, in contrast to Hans, who represents romantic love: "He's not the hearts and roses kind of guy; he's like the real deal." Lee commented that this is best expressed in the trolls' song "Fixer Upper", which shows that despite being far from perfect, Kristoff has been raised with solid values, is there for Anna when she needs him, and also calls her out when she makes mistakes: "I think you have to be able to do that in a relationship." Groff commented that Kristoff and Anna's relationship is an "unexpected romance" that begins like a business transaction before developing into a friendship. He thought that this sends a positive message to children that the couple get to know each other before falling in love.

Sven is Kristoff's best friend and also acts as his conscience. Lee conceived the idea of Kristoff talking for Sven in a simulated voice due to talking for her cat at home. Buck agreed with the idea, saying that he also talks for his dog, and loved the idea that when Sven finally speaks, Kristoff pretends that he does not understand him. Groff described Kristoff's habit of expressing his emotions through Sven's voice in the Frozen song "Reindeer(s) Are Better Than People" as a "weird personality quirk". This later inspired Kristoff's song "Lost in the Woods", a 1980s-style soft rock song in Frozen II. Songwriter Kristen Anderson-Lopez decided that Groff should have more opportunity to sing in Frozen II, but developing a song for Kristoff proved to be a challenge due to him being a gruff, reclusive character. Groff said that initially he could not imagine a mountain man like Kristoff breaking out into song. A comedy song titled "Get This Right" was previously written for Kristoff, which centred on him putting pressure on himself, but it was abandoned. Anderson-Lopez drew inspiration from "a lot of drunk dudes singing Journey at karaoke" to convey a man expressing his feelings. "Lost in the Woods" uses Kristoff's relationship with Sven by incorporating a chorus of reindeers, which Groff also voiced. Anderson-Lopez said that Kristoff's solitary life in the woods parallels Anna's solitary life living in the castle, which results in two socially awkward people coming together and having the inability to express their feelings. Groff felt that the comedy in Kristoff's song would help young boys to better accept Kristoff's emotions and also help them to express their own feelings.

Lee said that to write the song, they had to get inside Kristoff's head and felt that a passionate '80s ballad expresses the depth of his emotions: "He does right by Anna. He is a hero to me, in that way." Groff said that for Kristoff's song he worked with the composers to find the right balance between humour and sincerity: "He's really going through it." He described Kristoff as a "Disney leading man with a sensitive side" and said that in Frozen II his role inverts the trope of the male character setting off on an adventure, while the female pines alone at home. In the film, Anna sets off on an adventure, while Kristoff sings about his love for her and offers her support. Groff noted that, although he appears at the end to protect Anna from the giants, Kristoff does not take control or steal the spotlight, but simply asks her what she needs. He commented that Kristoff is "an example for women of what they deserve and for men to take a page from Kristoff's book". When he finally proposes to Anna, it comes "from the heart". Groff said that he feels self-conscious due to the failure of his past three proposals to her, but it was just the "right moment". Although their marriage would technically make Kristoff a king, he has no personal ambitions.

Design