Any and every fan of battle comics and manga has at some point probably asked themselves, "How much damage can my favorite character do with an attack?" This simple and ubiquitous question, lingering within the minds of shonen audiences, manifests as a most fundamental division within the field of power-scaling, i.e. the hierarchical analysis of a narrative and its characters/subjects.
For the purposes of this discussion, power-scalers can understand this subject by looking at Shonen Jump's Naruto Uzumaki and the metatextual controversy surrounding his true power. Those who engage in the conversation regarding Naruto have taken years to resolve the question of whether or not Konohagakure's Seventh Hokage could destroy a planet.
Planetary Defined
Before making a judgment on Naruto's capabilities, it's best to understand how real scalers extrapolate the metrics of fictional actions when such metrics are not explicitly stated or demonstrated. That is to say, battle-literators use a variety of methods, from "pixel-scaling" (extrapolating sizes of fictional items by using the page/panel as a reference scale) to "calc-stacking" (extrapolating data based on previously given or calculated data) in order to extract quantitative data from a largely qualitative medium.
When power-scaling characters based on their physical ability, the most relevant statistics tend to be speed and strength, meaning that most relevant data tends to be derived through joules (j), the standard unit of energy, and 'meters per second' (m/s), the standard of velocity. Using calculations to convert fictional feats into quantitative data, battle-literators are able to form objective baselines for the feats presented by the author -- for example:
If Hokage Naruto can destroy Earth, with no reason to assume Kishimoto's Earth is sized different from the Earth, then he would objectively be able to output at least around 2.25 x 10^32 joules.
Scalers find it easiest to categorize quantifiable feats of strength, leading to the formation of general tiers ranging from 'planetary' to 'universal' and beyond, all defined by the extrapolation of joule output. Although these terms are often understood and used colloquially, for these purposes, the prevailing definition of being planetary isn't necessarily being able to destroy a planet, but being able to output approximately 2.25 x 10^32 joules -- the energy it would take to destroy Earth beyond its gravitational binding energy.
How to Interpret Damage Metrics
After grasping the basics of quantifying fiction, it's reasonable to wonder why characters who are proclaimed to be planetary and beyond don't consistently destroy their planets with wild attacks. However, it's important to remember that just because a character hasn't done something doesn't mean they can't. Yet the true core of this subject rests within the limitations or strengths of the medium and the ways authors have taken to expressing battle-centric narratives.
The easiest metric of damage to determine is known as Destructive Capacity, or DC, because damage expressed through DC mirrors the physical rules of reality. Destructive Capacity is a gauge of the joules of physical actions in ratio to the impact felt by the surroundings (a.k.a. area of effect), e.g. an attack launched with 2.25 x 10^32 joules that destroys a planet has a 100% DC ratio. In reality, all actions have a 100% DC ratio due to the various laws of conservation that form our understanding of the universe.
Conversely, Attack Potency, or AP, can often be tricky when quantifying feats, as it highlights a key difference between reality and nearly all fiction in that these stories, especially battle manga and anime, often disregard the laws of conservation by design. A clever author can implement AP systems to allow characters to manipulate yottajoules upon yottajoules without ravaging the story's setting, all while maintaining the narrative's internal consistency. AP gauges a feat's quantitative value regardless of DC.
In stories with more developed "power systems," like Naruto or HunterxHunter, characters often express feats and deal damage that circumvents quantitative measuring by utilizing abilities commonly known as Hax. These Hax abilities can come in nearly any form, from Janemba's reality manipulation to Nagato's soul steal, and although they may be resisted in-verse, these feats can often not be quantified.
Damage Metrics as Narrative Tools
Because fiction mirrors reality, authors like Kishimoto must think carefully about how to highlight the fantastic elements of fiction while maintaining a sense of reality that allows the audience to invest in it. Narrative elements such as Naruto's "Chakra Control" and Dragon Ball's "Ki Control" serve as perfect examples of mangaka implementing narrative tools in order to raise the scale of a series' feats while maintaining the world's consistency.
As the battle genre becomes more defined, the tropes and key elements of the artform become more intricate, resulting in the aforementioned Hax abilities and nuanced feats that lead to more subjective interpretations and thus, complicated scaling. Series like Togashi's HunterxHunter and Akutami's Jujutsu Kaisen encapsulate this evolution of shonen feats with highly detailed power systems that serve as selling points unto themselves.
With all this in mind, the complexity of examining Naruto's ability to destroy a planet should become more clear, with his on-panel destructive feats not necessarily serving as limitations due to the narrative element, Attack Potency, as expressed through Kishimoto's tool, Chakra Control. Based on the evidence, including Kishimoto's approved statements in the databook, on-panel feats and scaling against Kaguya and Toneri Otsutsuki and direct appraisals of Kinshiki, the preponderance of evidence points to Hokage Naruto being able to destroy a planet -- and many times over at that.
