As generally written? As smart as a loaf of bread.
His intellectual capacity varies widely depending on who’s writing him.
But that’s not his fault. He’s afflicted with Plot Induced Stupidity at least once an issue. When you’ve got a guy who can bounce bullets off his chest, lift an ocean liner, out-calculate a computer, and be faster than a beam of light on a good day, he has to mess up before you can start your story.
- Genetically speaking? He’s descended from the genetically-enhanced genome of a super-intelligent species and whose parents were at the top of the food chain among them. He should be one of the smartest beings on the planet, Lex Luthor, Ray Palmer and Batman included.
- Given Superman’s/Kal-El’s parents being considered as 8th level intellects (we’ll get back to that in a moment) Superman must at least possess the POTENTIAL to be an 8th level intellect and even untrained would still likely possess the intellectual capacity to be one of the most intelligent beings living on the DCU Earth.
- Given some of his intellectual feats he should be able to claim a seat at any table at Mensa right alongside Lex Luthor and Bruce Wayne. We’ll get to some of those later.
This page clipped from Action Comics #3, page 4 is shown quoting Jor-El’s considerable intellectual capacity.
DC has defined Jor-El and Lara being lead scientists on the planetary Science Council.

Defining Intellect in the DC Universe

- Some are creative geniuses, capable of creating and envisioning new sciences often without equals: Metron, Lex Luthor, John Henry Irons, Mr. Terrific, Ray Palmer, Gorilla Grodd.

- Others possess mechanical or engineering geniuses capable of creating new, often unique machines or artificial intelligences: Professor Ivo, Will Magnus, T.O Morrow, Hiro Okamura, Victor Stone and the Brain.

- A number possess situational, physical, or other intellectual talents due to their longevity, physical training or other intellectual enhancement: Darkseid, Superman, Adam Blake (Captain Comet), Joker, Vandal Savage, Bruce Wayne, Terry Sloane, Doc Savage, Lady Shiva, Bronze Tiger, and Richard Dragon.

A holdover from the previous DC Universe
One such measuring tool was the use of the “genius levels of intellect” scale rated from one to twelve, with twelve being the maximum. Yes, there are rumors of a 16th level intellect but canon writings only take the scale to 12. Given the difficulties in determining how such intellects are rated:
- There is no objective scale that has been clearly determined
- The five known measures are still highly subjective
The five markers set down by DC in the previous continuities of the DC Universe were:
Highest level of genius intellect currently defined is a 12th level intellect.
- this has been displayed as the ability to consciously have 12 simultaneous thought processes at a genius level of intellect being performed concurrently.
- Intellectual capacity at that level is capable of developing sciences and concepts beyond the comprehensions of even other known geniuses and associated with the potential to master an unlimited number of disciplines.
- Such intellects are capable of memorizing entire libraries of information, multitasking and building entire mental simulations with the speed and accuracy of supercomputers. It has been hinted, however, that intellects at a level greater than ten are inherently unstable and prone to erratic behavior.
- Brainiac 5 of the Legion of Superheroes, and the original planetary computing machine Brainiac are considered to be at this level. Silver Age Brainiac (depicted below) and his more machine-like aspect in the late Post-Crisis and in the New 52 Universe are also considered to be one of the most intelligent beings in the Universe. However, things outside our Universe could, conceivably be more intelligent. (See: Metron.)
Brainiac is from the planet Colu. His “Twelfth-Level intelligence” makes him the smartest being in the entire Universe. He is also the coldest. From shrinking cities to annihilating entire alien races, Brainiac views the Universe as his own personal lab and will commit any act in the name of science. He is also especially fascinated with Superman and his wealth of Kryptonian Knowledge. This version of Brainiac was obsessed with all things Kryptonian and the Silver Age Superman was significantly more scientifically adept than any version of the character since the Crisis on Infinite Earths. Superman has been shown far less intellectually capable since the Man of Steel series in 1986.
- The entire 31st century Earth’s population is considered to be at a 9th level of intellect. Future Earth, super-smart general level of intelligence for Humanity on Earth. But this was the collective intellect of the species. Which probably means individuals were only at 6th or 7th level with the outliers pushing the numbers collectively higher. But this implies any citizen of the 31st century was smarter than ANY average citizen of the 20th century by a wide margin.
- The scientist Jor-El of Krypton was individually considered at the 8th level of intellect.
- The average citizen of Colu is individually considered to be at the 8th level of intellect.
- The entire 21st century Earth’s population is considered to be at a 6th level of intellect.
- One last marker: Lex Luthor has been estimated of being a 7-9th level intellect and arguably one of the smartest humans on the DC Earth.
Given these ratings and the recent reveal that Jor-El is at least an 8th level intellect and considered by “The Collector” to be Krypton’s leading scientific mind, and Lara was also considered a first rate scientist on Krypton, this means Kal-El has the genetic potential to be considered a genius of that order.
Assuredly with his mind’s enhancement under a yellow sun, he is certain capable of being one of the most intelligent beings on the DC Earth. His greatest weakness is likely a lack of significant exposure to information and education to challenge his intellect to achieve its greatest state. In the modern DC Universe, Superman has been shown to use his natural aptitutes for skill acquisition and super computation in addition to a genius-level aptitude with using his powers and abilities.

Is Superman’s thinking affected by his powers?
In the canon DC Universes, Superman’s raw intelligence is considerable but rarely challenged. Kal-El is the son of two of Krypton’s top scientists but his time on Earth, in most continuities, he is not challenged to utilize his super-intellect to its greatest capacity.
One of the greatest standard display of his super-intellect is his Fortress of Solitude. Pre-Crisis, Silver-Age Superman, particularly in the 1960s and early 1970s was the most scientifically inquisitive and skilled version of the character.

- He built his Fortress of Solitude by himself, no Kryptonian super-crystals as seen in the Donner Superman movies.
- He created a shrink-ray so that he could visit the Bottle City of Kandor, shrunken by the evil Brainiac. He would also create a technology for the Kandorians to be free of their bottle prison.
- He tended a zoo of alien animals he saved from extinction within the Fortress. No idea how he made food for them, but they always looked health and exotic…
- He created his Superman robots to help tend the Fortress, stand in for him when he needed to protect his secret-identity and to assist him when he needed to assist in more than one place at one time.

- While the robots lacked all of his abilities, they were quite capable of standing in for him for most issues. They did possess a degree of superhuman strength, flight and heat vision. He also programmed their artificial intelligence.
- He maintained a laboratory where he conducted experiments (of an unknown nature), he maintained an armory of super-weapons from all over the known galaxy, and occasionally built devices (the Supermobile and other exotic equipment).
- He also maintained a communication array that he used to talk with aliens all over the galaxy.



Post-Crisis Superman
Superman, as he has been written from the Post Crisis Era to the last iteration of the DC Universe, was not considered to have as great a superhuman intellect. The early Post-Crisis version of the character by John Byrne was meant to emphasis the MAN, not the SUPER, so his life as Clark Kent was the focus of these early stories.
- However, he would rediscover technologies from Krypton, utilize them as he needed and archive them within the Fortress of Solitude. He would rebuild his Fortress a number of times to improve security.
- He would also use hybridized Kryptonian and human technology created by John Henry Irons (aka Steel) and would also utilize alien technologies over time (Thanagarian).

- Whether this will remain true in the latest DCnU remains to be seen. Lacking a super-human intellect did not mean he was not intelligent, after all he was the son of the greatest scientists of Krypton, Jor-El and Lara-El. But he did not get the grounding in science he would have needed to equal his parents capabilities. His current Fortress is still an impregnable stronghold filled with technology from all over the galaxy. While he may not be considered a super-genius, his ability must be significant enough he is able to rebuild and maintain his Kryptonian stronghold on Earth.
That said, it is obvious that his natural abilities far exceed a Human’s for a variety of reasons he displays every time he uses his powers.
- He does possess a photographic memory.
- He is able to remember everything he has read and can draw upon it at will.
- He has taught himself surgery, at superspeed no less. It is theorized, if he made the effort he could learn and retain any particular skill he had an interest in applying himself to.

- It is unclear if this is a byproduct of his powers or a natural Kryptonian ability. He is also able to speak every language he has encountered or bothered to learn.
- His brain must process its activity and neural connectivity at a rate far greater than ours.
- This can be surmised by the fact that he is able to utilize super-speed with both precision and accuracy and has done so pretty much from the beginning of his media career.

- Once he adapted to Flash’s movement, he was able to turn the tide and predict his movement, much to Flash’s chagrin.
- This was displayed most often during his Pre-Crisis era when he would have a yearly race with the Flash around the world.
- Their challenge was to keep the race sub-sonic because Superman would case catastrophic damage as he pass areas creating sonic booms. (The Flash does not have this problem, because of his speed aura. He only creates sonic booms if he wants to.)
Superior Proprioception :
- Since Superman can control his bodily movement and proprioception (his awareness of where his body is in space) with pinpoint accuracy, it stands to reason his brain’s processing speed and neural activity are both faster, more precise, better networked, and able to be controlled at a level far better than a Human brain.
- Since it is unlikely, but not necessarily impossible, for his brain to speed up the flow of electrical activity past what the normal brain can, it is more probable he has a greater neural density, allowing more neural pathways for the signals to pass through.
More neural connections, more conceivable brainpower
- Having a greater network density could conceivably give Superman the potential for improved cognitive ability, especially if both sides of his brain are connected by a thick bundle of neural materials (in Human’s this is the corpus callosum) which coordinates activity between the left and right sides of the human brain.

- Since we have never been given access to the Kryptonian brain, we make assumptions it is much like the Human brain. But even subtle differences could give Superman far greater abilities.
- Modifying the density of the barriers between the halves of the human brain would allow a human increased language capabilities, ambidexterity, incredible artistic and musical capabilities. If the Kryptonian brain were similar he would also have such increased abilities. Pre-Crisis Superman had all of these powers and more.
Instinctive, intuitive use of superhuman abilities
- The most likely reason we would assume Superman (and by proxy all Kryptonians) have greater intellectual capacity is that their brains allow them to control their superhuman abilities at an intuitive level with only a few days of training.
- In the cases of physical fit, or well trained individuals, they are able to control their powers in hours. Precise control takes far longer, but for the ability to utilize their superhuman potential in a matter of days, implies their brains are far more sophisticated, capable of incredible feedback mechanisms and shows the Kryptonian brain to be a finely tuned organ.



In Summary
- If anything can be determined by this essay, the best thing we can determine is that Superman, the character, is rarely shown using all of his mental capacity as can be inferred by these ideas.
- Likely because, if he were written using his abilities to their fullest potential he would be even more difficult to write because it would remove him from his relationship to normal humans.
- Superman could be as smart or smarter than Batman if he applied himself the same say Bruce Wayne has. Theoretically if he had teachers on the caliber of the Kryptonians, he should be able to learn as much as his parents did or even more since he has exposure to technologies that he did not invent.
- The safest way to explain it is, since he aspires to be human, and possesses incredible natural talent, he has never tried to apply himself to see what ELSE he could do if he tried. Superman is a jock and writers are thankful for that.


Apocrypha: All-Star Superman
People often look at the graphic novel/movie version of “All-Star Superman” as a sample of Superman utilizing his superhuman intellect. While he does use his abilities to their fullest there, this particular Superman is an Elseworlds version of the character, not a mainstream continuity version. The DC Animated feature film All-Star Superman was based on the comic book series All-Star Superman.
As noted in Wikipedia:
- All-Star Superman is a twelve-issue comic book series featuring Superman that ran from November 2005 to October 2008. The series was written by Grant Morrison, drawn by Frank Quitely, digitally inked by Jamie Grant and published by DC Comics. DC claimed that this series would “strip down the Man of Steel to his timeless, essential elements”.
- The series was the second to be launched in 2005 under DC’s All-Star imprint, the first being All Star Batman and Robin the Boy Wonder. These series are attempts by DC to allow major comics creators a chance to tell stories showcasing these characters without being restricted by DC Universe continuity. [emphasis mine]
- The All Star Superman was not a single Superman but an amalgam or archetype of the iconic hero across his entire heritage encompassing all of his previous incarnations.
- This was done to allow a well known writer to try and expound on the legend of Superman unrestricted. Grant Morrison used elements from across the history of the character to create a single story that embodied every Age of Superman.
- All-Star Superman is not the canon character of Superman, he is the paragon of the archetype.

Parts of this essay originated on the Science Fiction and Fantasy Stack Exchange. I am the original author. All Rights Reserved.

Other Quora articles on the Man of Steel
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- What is the difference between the Pre-Crisis version of Superman and Post-Crisis version of Superman?