In the Naruto world, the leaders of the major villages are known as "Kage." To oversee the activities of their village, these ninjas must have exceptional combat prowess and leadership skills. Kage are the strongest fighters in their village, but there are a few notable exceptions.
For instance, during her time as the Fifth Hokage, Tsunade was inferior in power to Might Guy, Kakashi Hatake, Naruto Uzumaki, Jiraiya, and likely Danzo Shimura. Regardless, a ninja with the title of Kage is inherently implied to be mighty.
This thread will list all Kage, ranking them by their overall strength when they held the office. Thus, Kakashi will be considered without his Mangekyo Sharingan, not to mention the Six Paths chakra and the complete set of Obito's eyes, as he didn't have those powers during his reign as the Sixth Hokage.
Every Naruto Kage ranked from weakest to strongest
27) First Mizukage, Byakuren
Being the founder of the Hidden Mist, Byakuren was certainly a fearsome fighter. His abilities are mostly unknown, but it can be assumed that he was a skilled Water Release user.
26) First Tsuchikage, Ishikawa
As the man who established the Hidden Stone, Ishikawa was a mighty ninja, as well as a wise and experienced individual. Presumably, he was proficient with Earth Release techniques.
25) Third Mizukage
The Third Mizukage's techniques are yet to be revealed, and so is his name. Still, as the ninja who was chosen to lead the Hidden Mist after Gengetsu Hozuki's passing, he must have been a rather powerful man. Before becoming the Third Mizukage, he worked as the First's bodyguard, which is another testament to his might.
24) Second Kazekage, Shamon
The first renowned puppet user in the ninja world, Shamon led the Hidden Sand to achieve notable military expansion, in which the former's individual strength likely played a major role. Even before being appointed for the position, he was regarded as strong enough to be the bodyguard for the First Kazekage.
23) First Kazekage, Reto
So far, the exact amount of Reto's power, as well as his techniques, are unknown. Still, the fact that he was able to unify all of the desert-dwelling ninjas under his leadership implies that he was a mighty individual.
22) First Raikage, A
As the Warring States Period headed to an end, the First Raikage led the nascent Hidden Cloud Village. He is the one who sent Kinkaku and Ginkaku to capture the Nine Tails.
21) Second Raikage, A
Before becoming the Second Raikage, A was chosen as his predecessor's bodyguard. He worked to create an alliance between the Cloud and the Leaf, but he and the Second Hokage Tobirama were ambushed by Kinkaku and Ginkaku. Tobirama barely managed to survive the assassination attempt, while the Raikage's fate is unknown.
20) Fourth Tsuchikage, Kurotsuchi (Post War)
A specialist of elemental ninjutsu, Kurotsuchi served the Third Tsuchikage Onoki, who was also her grandfather, as his bodyguard. During the Fourth Ninja War, she fought the White Zetsu Army alongside Kitsuchi. After Onoki's retirement, Kurotsuchi became the new Tsuchikage.
Kurotsuchi can use Earth Release to hide underground, erect rock domes, launch her enemies from underground or attack them with sharp spikes. She can also combine Lava Release to restrain opponents, either covering them with ash or creating quicklime, which she hardens via Water Release.
19) Fourth Kazekage, Rasa
Employing his Gold Dust, Rasa was able to subdue the fully released One Tail Shukaku, which he later sealed into his youngest son, Gaara. Gold Dust enables Rasa to defend himself via thick barricades or crash his foes under colossal waves. However, his techniques couldn't protect him from Orochimaru, who killed him.
18) Third Kazekage
At least until the beginning of Naruto Shippuden, the Third Kazekage was the strongest ninja in the Hidden Sand's history. He could manipulate iron powder by converting his chakra into magnetic forces. As such, he created the Iron Sand, which made him immune to all metallic weapons.
Assaulted by Sasori, the Third Kazekage used the Iron Sand to clog the joints of puppets, rendering them useless. However, he was still beaten and killed by Sasori, who, aiming to use the Iron Sand, turned his corpse into a human puppet at his disposal.
17) Sixth Mizukage, Chojuro (Post War)
A former member of the Seven Ninja Swordsmen of the Mist as well as the previous Mizukage's bodyguard, Chojuro is a proficient fighter who was selected to be the Sixth Mizukage. He can store his chakra in his dual-handled sword, Hiramekarei, and then suddenly release it to perform tremendous slashes.
16) Fifth Mizukage, Mei Terumi
Fifth Mizukage Mei Terumi is a highly skilled specialist in elemental ninjutsu. She can perform Water Release techniques on a large scale even without a pre-existing water source. Moreover, she can use two elemental Kekkei Genkai.
With Lava Release, she can spit out acidic mud, while Boil Release allows her to release a corrosive mist. Both abilities have extremely high melting powers. Although a dangerous individual in her own right, Mei is widely considered the weakest among the Five Kage who were in charge during the Fourth Ninja War.
15) Fifth Hokage, Tsunade
One of the Leaf's Three Legendary Ninjas and an offspring of the Senju clan, Tsunade is an exceptional medical ninja. She can dish devastating punches, kicks, and other physical blows. While particularly powerful, however, the Fifth Hokage's blows are relatively easy to dodge for ninjas who are fast or can use elusive techniques.
Still, factoring in her Byakugo, which allows her to quickly heal even fatal wounds by releasing her stored chakra, Tsunade must not be underestimated. She can endure most attacks and then bulldoze through them. In battle, Tsunade can also summon Katsuyu, a giant slug who can boost her healing abilities.
14) Fourth Mizukage, Yagura Karatachi
Yagura mastered the powers of the Three Tails Isobu, becoming a perfect jinchuriki. As such, he could use Isobu's chakra and transformations, including the Coral Palm, a technique that restricts the opponent's movements, and even the ravaging Tailed Beast Bomb.
A Water Release expert, Yagura could use the Aqua Mirror Jutsu, which materializes reflections that replicate the target's own techniques, to counter their attacks. At one point, Obito Uchiha used his Sharingan powers to take control of Yagura. Sadly, the possession turned out to be fatal for the young Mizukage.
13) Fifth Raikage, Darui (Post War)
The Fourth Raikage's bodyguard and right-hand man, Darui, was chosen to lead the First Division of the Allied Shinobi Forces. He showcased notable skill, fending off Kinkaku and Ginkaku, although he found himself overpowered by their Tailed Beast transformations. Eventually, he became the Fifth Raikage.
Darui is rather fast, as he could coordinate his movements with the Lightning Release Chakra Mode-empowered Fourth Raikage. A highly proficient ninjutsu user, Darui can combine Water Release and Lightning Release. He can also use Storm Release to fire beams of light, which he can guide toward the target.
A disciple of the Third Raikage, Darui can use the same "Black Lightning" as his teacher. Thus, he can perform techniques such as the Lightning Release: Black Panther, which is stronger than the average elemental attacks.
12) Fifth Kazekage, Gaara
As the jinchuriki of the One Tail Shukaku, Gaara was trained to be the Hidden Sand's ultimate human weapon. However, after meeting Naruto Uzumaki, he managed to leave his terrifying past behind and rise as the Fifth Kazekage.
By manipulating sand, Gaara can simultaneously defend himself and overwhelm his enemies. Even after the One Tail was removed from his body, Gaara's abilities didn't diminish but, over time, even improved, to the point where his skills were directly compared to Shukaku's.
Infusing sand with chakra, Gaara's techniques are especially effective, as he could even block Sasuke's Blaze Release flames. During the Fourth Ninja War, Gaara beat his father, the Fourth Kazekage, and then assisted Onoki against Mu and Gengetsu. Still, they didn't stand a chance against Madara.
11) Fourth Raikage, A
A fearsome brawler who combines ninjutsu and taijutsu, the Fourth Raikage can empower himself via the Lightning Release Chakra Mode. This technique notably boosts his capabilities, allowing him to gain chakra levels comparable to a Tailed Beast. While in this state, the Raikage stands out with regard to speed, durability, and physical strength.
10) Third Tsuchikage, Onoki
Acknowledged by Madara as the main threat among the Five Kage who tried to challenge him, Onoki was a great shinobi. Even at more than 80 years old, his combat prowess was notable. A master of Earth Release, Onoki could employ great defensive moves as well as peculiar techniques to increase or decrease any target's weight.
As such, he could even become light enough to fly at the same speed as Deidara. Onoki was also able to use the very rare Dust Release, which can pulverize any target it hits into dust. However, due to his old age, the Third Tsuchikage had relatively little stamina.
9) Second Mizukage, Gengetsu Hozuki
A master of Hozuki's Hydrification Technique, Gengetsu's most dangerous jutsu was the Steaming Danger Tyranny, a water clone that moves at high speed. Surrounded by a thin outer layer of oil, it generates a never-ending series of violent explosions. He could also perform genjutsu to hide his actual location via mirages. Mu's archenemy, the two eventually ended up killing each other.
8) Second Tsuchikage, Mu
An experienced user of Earth Release and Dust Release, Mu could also perform a technique to split himself into two duplicates, which allowed him to avoid incoming lethal blows and continue fighting. However, his overall strength would also be split in half.
Mu was known as the "Null-Man" due to a special jutsu he used to turn himself invisible, erasing his presence to the point where even sensors couldn't track him. After a fierce battle, Mu killed the Second Mizukage, but at the cost of his own life, which he lost in the process.
7) Third Raikage, A
Owing to his insanely durable body, which he could further empower with the Lightning Release Chakra Mode, the Third Raikage was a force to be reckoned with. His strongest jutsu, the Hell Stab, was simply devastating. A testament to his immense might, he could fight Gyuki, the Eight Tails, to a standstill. He was also able to fend off an army of ten thousand ninjas by himself.
6) Third Hokage, Hiruzen Sarutobi (Prime)
Renowned as "The Professor" for his ability to use countless techniques, including the Dead Demon Consuming Seal and all five chakra natures, in his prime days Hiruzen was the strongest Kage of his generation.
As he aged, his battle prowess significantly diminished, especially with regard to his stamina. Still, he remained strong enough to fend off Orochimaru, who even declared that Hiruzen would have defeated him had he been just ten years younger.
5) Second Hokage, Tobirama Senju
A crafty shinobi, Tobirama could use Water Release to a very advanced level. He created the Flying Thunder God, which he used in combo with the Shadow Clone Technique to blitz his enemies. Tobirama beat and killed Izuna Uchiha, whose abilities were comparable to those of his brother Madara before the latter evolved his Sharingan.
Tobirama also created the Impure World Reincarnation. By summoning corpses, he used to have them explode continuously via the Mutually Multiplying Explosive Tags, which allowed him to perform destructive attacks one after another.
4) Fourth Hokage, Minato Namikaze
Few ninjas can ever be compared to Minato. Owing to the Flying Thunder God Technique, which enabled him to instantly teleport everywhere he put his mark on, Minato earned himself the moniker "Yellow Flash". Even the Raikage stood no chance against him.
Minato could use barrier techniques, even in combination with the Flying Thunder God, as well as sealing techniques, including the Dead Demon Consuming Seal and the Uzumaki clan's moves. As the creator of the iconic Rasengan jutsu, he could also employ Jiraiya's toad summonings.
Minato single-handedly defeated Obito and fended off the Nine Tails, protecting the Hidden Leaf. He ultimately sacrificed his life to seal half of the Tailed Beast into his newborn son. Immediately before his death, Minato became the jinchuriki of the beast's other half, a power that he couldn't use until his soul was temporarily reincarnated.
3) Sixth Hokage, Kakashi Hatake (No Sharingan, Post War)
After being recommended for the position many times, Kakashi eventually became Hokage, even though he didn't have his Sharingan anymore. Upon mastering that eye power, Kakashi could use Kamui to instantly warp anything into another dimension. His prowess earned praise even from Madara.
As Obito entrusted him with his Six Paths chakra and visual powers, Kakashi gained flawless defense and unstoppable offense, which made him virtually invincible. He single-handedly fended off Kaguya Otsutsuki, showing much better feats than even Naruto's and Sasuke's. However, this power expired and can never be obtained again.
As the Sixth Hokage, Kakashi was stated to be stronger than his War Arc self with one Mangekyo Sharingan, which was impressively powerful. To make up for the loss of Kamui's space-time hax and the inability to use Lightning Cutter, Kakashi reached the highest level that a ninja can achieve without eye powers or special chakra.
He created the mighty Purple Lightning as well as the Fire Release: Water Mist, an insanely strong move that crushed a Six Paths-enhanced Water Release jutsu despite the elemental disadvantage. He also evolved his Earth Release into the Quartz Wall, which can cover an entire village. Simply put, Hokage Kakashi is like "prime" Hiruzen but much stronger.
2) First Hokage, Hashirama Senju
The original user of the Wood Release, Hashirama, could perform techniques on a totally different scale than anyone else, to the point where his might was considered a fairy tale. Further empowering his moves with Sage Mode, he single-handedly overwhelmed the ravaging combination of Madara's Perfect Susanoo and the Nine Tails.
Exceptionally proficient in every aspect of combat, Hashirama had incredible life force and stamina. His chakra was almost unlimited, and he could regenerate his wounds nearly instantly. Before the final events of the Fourth Ninja War, no ninja was as strong as the legendary "God of Shinobi".
1) Seventh Hokage, Naruto Uzumaki (Six Paths Sage Mode)
Naruto eventually mastered the chakra of the Nine Tails, whom he had sealed in his body since he was born. Tenacious and unpredictable, he is a relentless fighter who never gives up until he beats his opponent, either flanking them with the Shadow Clone Technique or overpowering them with mighty moves such as Rasengan, Rasenshuriken, and Tailed Beast Bomb.
During the Fourth Ninja War, Hagoromo Otsutsuki gifted Naruto with the Six Paths Sage Mode. As such, all of the young ninja's abilities were enormously empowered. Moreover, he also learned to fly and float and perform new techniques, such as Truth Seeking Balls and Multiple Tailed Beast Bomb Rasenshuriken.
Fulfilling his role as Ashura Otsutsuki's reincarnation, Naruto on his own had enough might to match Sasuke, who was using the Six Paths-enhanced Rinnegan plus the chakra of all nine Tailed Beasts. Towards the end of the series, Naruto deservedly realized his dream of becoming a Hokage.
Final Thoughts
Each Kage has their own fighting style, with different skills and techniques. As such, while all village leaders are mighty ninjas in their own right, there may be significant gaps in power between them.
For the most part, Hokage are stronger than their counterparts from the other villages, i.e., Raikage, Tsuchikage, Kazekage, and Mizukage, but depending on the generation, there may be some exceptions.