There are plenty of iconic anime transformations across the ages. Whether it's Goku's Super Saiyan transformation from Dragon Ball Z, Sailor Moon's transformation sequence, Luffy's Gears, or Yugi Moto transforming into Yami Yugi, everyone has at least one they consider iconic.
While plenty of anime have come and gone, many iconic transformations stand the test of time and are still worth witnessing. Narrowing a list down to 10 iconic transformations across the wealth of anime that have come out seems impossible. Therefore, some are left out and they are ranked by their significance to the story being told as well as their iconic status outside their series.
Disclaimer: The following article contains spoilers for all the anime discussed. All opinions are exclusive to the author.
10 iconic anime transformations, ranked by significance
10) Digivolution (Digimon)
Digivolution refers to the way that Digimon evolve throughout the Digimon franchise. Digivolution occurs when Digimon absorb enough data to grow past their present state, going from Digieggs to Rookies to Champions to Mega in tiers. It requires absorbing enough data and having enough strength to retain it.
Digivolution is an iconic anime transformation and a staple of Digimon. It's effective at saving the various Digidestined, getting powerful Digimon like Wargreymon to help them against large threats. Digivolution's significance to the series is "the power of friendship," since the Digidestined's Digimon digivolve faster.
Thanks to faster digivolution, they also use fusion to battle ever-tougher foes. All of this ultimately ranks Digivolution higher than Pokémon evolution, at least as far as their respective anime are concerned. Digimon is practically known for the digivolutions outside the series, as Agumon may be a mascot but most of the marketing focuses on higher evolved states.
9) Hollow Ichigo (Bleach)

From Nelliel's transformations from her kid form to her adult form to the various Arrancar like Ulquiorra Cifer, Bleach has many iconic anime transformations that could've easily made the list. Main protagonist Ichigo Kurosaki's Hollow form, however, made the list because it's one of Ichigo's first and most iconic transformations.
One other note that makes the Hollow form Ichigo's most iconic anime transformation is the story around it. Ichigo's Inner Hollow is much like Kurama from Naruto: a sadistic and Darwinistic being named Zangetsu. The significance is from possession, as Zangetsu attempts to possess Ichigo multiple times.
The significance is that Ichigo has to battle his inner despair and manifestations of his Quincy and Soul Reaper powers. Zangetsu is finally brought to care and respect Ichigo by the time of the Thousand Year Blood War.
8) Yami Yugi (Yu-Gi-Oh!)

When Yugi Moto solved the Millennium Puzzle and inserted the final piece, his life changed forever. Yugi found himself sharing a body with a pharaoh from Ancient Egypt called Atem, aka Yami Yugi. At the start of the manga, Atem routinely possessed Yugi's body to punish bullies. Yugi would retain little to no memory of the events.
Much like Clark Kent changing into Superman, Yugi's iconic anime transformation is significant because of how much he changes. He gets slightly taller, his voice gains confidence, and Yami takes over with his brilliant mind and strategies. This is opposed to Yugi being a meek teenager normally, who can barely fend off a bully.
The added music, spinning Millennium Puzzle, and the "Yu-Gi-Oh!" cry during the transformation in the anime help cement its place as iconic anime transformation. Its significance isn't lost throughout the series, as Atem's history is uncovered as Yu-Gi-Oh! progresses. Outside of the series, Yami Yugi features prominently in video games and marketing for the card game.
7) The Jusenkyo Curse (Ranma 1/2)

Ranma 1/2 features its own iconic anime transformation, a gender changing protagonist. Ranma Saotome found himself cursed to change into a girl when exposed to cold water and then back to a man when exposed to hot water after an incident in the Junsekyo hot springs.
This transformation is iconic for several reasons. The first being that it's the inciting incident for the rest of the series, Ranma dealing with the curse also brings with it a ton of suitors trying to get at him, whether in male or female form. The second is how it contributed to LGBT+ representation in the 1990s.
While Ranma's goal is to get rid of the curse, the transformation itself remains iconic for the fact that it's a genderbend as opposed to crossdressing. Not many anime or manga did that in the 1990s, much less made it the focus of the plot.
6) Gon's transformation (Hunter x Hunter)

A case of a one-time transformation that took a character out, Gon of Hunter x Hunter forced his transformation during the Chimera Ant arc. Gon's is a subversion of most anime transformations: it allowed him to go to full power, but it also disabled his ability to use Nen.
It comes up this high because, despite the prior transformations being staples of their series, this one is significant enough in the story to cause a protagonist shift from Gon to Killua. The context behind the transformation is that during the Chimera Ant arc, Gon became increasingly angered by Pitou's actions (especially killing Kite) and vowed to kill them.
It resulted in Gon's flaws manifesting when he finally beat Pitou into paste. Although Gon transformed into an adult and gained the strength to accomplish his goal, his body wasn't prepared or equipped for that magnitude of power. He lost an arm, was in a coma, and is stuck back home doing all the schoolwork he missed while Killua continues as the protagonist.
5) The Sailor Senshi transformations (Sailor Moon)
Sailor Moon is one of the most iconic magical girl franchises throughout the genre's history. The Sailor Senshi's transformations considered iconic anime transformations for how they happen in almost every episode, and their significance in the story. Every one of the Sailor Guardians, save for Chibi Moon and the Starlights, reincarnated from powerful people from eons past.
Usagi Tsukino, for example, is the reincarnated version of Princess Serenity from the Moon Kingdom. This plays into the story as early as the first episode. Usagi's memories of being Princess Serenity are slowly unlocked as the series progresses. The transformed states are usually front-and-center when Sailor Moon is advertised, Usagi's especially since she's the titular Sailor Moon.
It helps that every transformation is different and progresses in complexity and imagery as the series progresses. Outside the series, the magical girl genre owes Sailor Moon for breaking into the mainstream. Despite other magical girl series like Cardcaptor Sakura and Magical Girl Lyrical Nanoha and deconstructions like Madoka having devout fanbases, most fans point to Sailor Moon when they think of magical girls and transformations.
4) Nine-Tails Chakra Mode (Naruto)

The nine-tailed fox Kurama was sealed inside Naruto Uzumaki during infancy. In times of distress, Kurama lends Naruto power via an iconic anime transformation: The Nine-Tails Chakra Cloak. The Nine-Tails Cloak is Kurama's chakra, which boosts his host's power exponentially.
It changes Naruto's appearance: in the first form, it makes his whiskers sharper and more pronounced, his teeth grow fangs, his nails grow into claws, and his strikes hit harder. This progresses until Naruto is more bestial in appearance, with a set number of tails representing Kurama taking further control.
The significance of this iconic anime transformation is shown across the series, being a visual representation of Naruto and Kurama's relationship. They start mutually hostile, and it's not until the end of Shippuden that Naruto and Kurama become allies and friends. This is represented by the Nine Tails Chakra Mode being warm-colored and Naruto completely controlling the powers.
3) Luffy's Gears (One Piece)

Monkey D. Luffy is already iconic due to his Devil Fruit turning him rubber-like. Gear 5 became an iconic anime transformation on the internet when it was revealed, or at least utterly broke the One Piece fandom, for its usage of cartoon physics against Kaido. However, the other Gears are significant in One Piece's plot and Luffy's development.
The significance is that Luffy learned to combine Haki with his Devil Fruit abilities, eventually realizing the true extent of his powers is to make whatever he can imagine into reality. Each Gear has its unique appearance and ability: Gear 2 sends out steam and boils his blood fast to adapt to blows, Gear 3 allows him to inflate his body, Gear 4 is a muscle form that renders him near impervious to damage, and Gear 5 turns everything into cartoon physics and makes Luffy look like a laughing god.
It's eventually pieced together that Luffy's Devil Fruit is a Mythical Zoan type. Luffy is likewise dubbed a reincarnation of the legendary Joy Boy owing to his heartbeast taking on "the drumbeat of liberation," key to the legend. Gear 5 was considered a triumph of storytelling by One Piece fans when it finally premiered.
2) Titan Shifting (Attack on Titan)

The most iconic shots from Attack on Titan exist thanks to Titan Shifting. This includes, but is not limited to: the Colossal Titan breaching Wall Maria, Annie's transformation into the Female Titan, Eren attacking the nation of Marley during the declaration of war, among others, like multiple people turning into Titans in the final season.
Aside from being an iconic anime transformation, Titan Shifting is one of the biggest mysteries and most horrifying revelations in Attack on Titan. Not only is it already horrifying to fight giant monsters that eat people, but finding out that people can turn and be turned into those monsters nearly breaks the minds of the Scout Division.
This is particularly true in Connie's village of Ragako, where the Beast Titan transformed the entire population into Titans. Aside from the horror factor, the significance of Titan Shifting extends outside of the series likewise: many of the Titans are used in advertising, as merchandise, and remain the reason Attack on Titan was considered one of the better anime of the 2010s.
1) The Super Saiyan Transformation (Dragon Ball Z)
The Dragon Ball franchise has had many transformations throughout its 40-year history, from the Great Ape to Frieza's various forms. Its iconic anime transformation is the Super Saiyan, so much so that Goku is constantly advertised as a Super Saiyan in everything from movies to video games and even parade floats.
The Super Saiyan's golden hair, golden aura, green eyes, and serious expression have been parodied, homaged, and referenced in pop culture worldwide since Goku first turned Super Saiyan in Dragon Ball Z episode 95 in 1991. The transformation in series has upgraded from the base Super Saiyan to get longer hair, different colors, and even godly forms to fight threats to the universe.
For many, the Super Saiyan transformation is the iconic anime transformation that every other anime with a transformation sequence or state has to compare to. While debates rage about which did it better, Dragon Ball's staying power well past its original anime cements that the Super Saiyan transformation will live on.
Final Thoughts

Although the iconic anime transformations on this list are significant, this list is not exhaustive. There are transformations like robots that transform into vehicles, as in Macross/Robotech. Soul Eater has spirits that take the form of weapons and go back and forth from human to weapon form.
Likewise, contemporary anime like Chainsaw Man and Demon Slayer have their own iconic anime transformations, My Hero Academia and Kaiju no 8 likewise. The point is that more than 10 iconic anime transformations could've made the list.
Whether from older or newer anime, transformations will be a staple of anime for years to come. Even if the art of transformations is normally regulated to shonen anime, the art of iconic anime transformations aren't exclusive to shonen.
Related Links
- 10 anime transformations that had the most impact on the story
- 10 most iconic Sailor Moon transformations ranked
- 10 transformations in Dragon Ball, ranked by difficulty