Sci Fi vs Fantasy: What’s The Real Difference?

What pops into your mind when you think of sci fi vs fantasy? Perhaps it's looming UFOs and gravity-defying dragons? Or rogue AI and potion-brewing elves? It’s true that both genres help readers to escape to extraordinary worlds, but what is it that really separates them from each other?

The short answer is that science fiction explores the possible through science and technology, while fantasy explores the impossible through magic and the supernatural. Though both are speculative, their approach to possibility, the extraordinary, and worldbuilding differ tremendously. 

As for the long answer, in this article, I’ll look closer at what truly makes these genres distinct, and even take a look at the times when their boundaries blur. Now, prepare to enter light speed — we’re diving into the first point of contrast: worldbuilding!

Worldbuilding rules

At the heart of the sci fi vs fantasy debate lies the important question: what speculative premise powers the story world?

As I mentioned before, science fiction builds on what is already possible. Although stories within this genre are sometimes far-fetched, they're always grounded in known or imagined scientific laws. They ask questions such as: what if the world was run by AI? Or, what if humans lived on Mars? 

In these worlds, you can expect to see:

• Futuristic technology: Think of the light-speed that I mentioned earlier. Or mind-computer interfaces.
• Rational speculation: Science fiction authors tend to ground imaginative scenarios with logical explanations, such as “What if we created synthetic life?”
• Technobabble: Aka fictional scientific jargon designed to feel as plausible as any real-life scientific theory. 

📚Example: The Martian. Andy Weir’s novel follows the unlikely story of Mark Watney, an astronaut who gets stranded on Mars and left to his own devices. Faced with the brutality of space, Mark is forced to use the complex technology around him and his scientific knowledge to survive — something that the average Joe might find slightly challenging.

 

Though this premise lies far from reality, it becomes much more believable with the help of science, logical thinking, duct tape, and a sprinkling of humorous human error — making the extraordinary feel pretty legit.

On the flip side, we have fantasy, which isn’t afraid to aim straight for the absurd or supernatural. These worlds are often built upon self-contained magical systems that may be well-defined, but don’t necessarily align with the natural logic of our world. 

Fantasy worlds are often built on the following: 

• Soft magic systems: A term established by author Brandon Sanderson, where magic is not used to solve problems — rather its sole purpose is to be awe-inspiring. Further, the rules of soft magic systems are loosely defined and readers don’t necessarily need to understand them in order to “get” the plot.
• Hard magic systems: By contrast, hard magic has a set of clear rules that the reader must understand, so that when it is used to solve problems, it doesn’t feel like magic is “saving the day” — rather, the characters' wit and critical thinking does.  
• Mythology, folklore, and the supernatural: You can often find creatures such as minotaurs, dragons, and gods wandering these fantastical lands. Or perhaps even an archaic artifact that, once dug up, administers a deadly curse to a character’s bloodline! Either way, these beasts and otherworldly powers are rarely bound by logic.

📚 Example: The Lord of the Rings. Arguably the most famous fantasy work ever written, J.R.R. Tolkien’s The Lord of The Rings is defined by prophecy, magic, and mythical creatures. It’s an especially shining example of soft magic, where Tolkien doesn’t waste time explaining how Gandalf’s magic works, instead highlighting the wonder and mystery that it inspires. 

Now that we know exactly what rules each of these genres do (or don’t) play by, let’s take a look at the differences between when and where they usually take place.

Timelines and settings 

Generally, science fiction uses an unexpected future or an alternate reality of our world to imagine where the wonders of technology might take us next.

Some typical locations include:

• 🌎A near-future earth: In these versions of Earth that aren’t too dissimilar from ours, we see the disastrous effects of climate crises, AI uprisings, and biotech revolutions. Example: (Spoilers ahead!) Kazuo Ishiguro’s award-winning novel Never Let Me Go follows three friends in a mysterious boarding school, where they discover that they’re clones being raised as organ donors for their “original.” Set in a world identical to ours, this story navigates the ethical consequences of cloning and what it means to be human.

• 👽A distant space opera: Impressive galactic empires and alien civilizations are also a tried-and-true science fiction setting. Example: In James S. A. Corey’s political thriller The Expanse, the solar system is colonized and home to a multitude of unique species.

• 🏰Alternate histories: The imagination of science fiction often goes a step further, speculating upon the different outcomes of known historical events. Example: In the alternative version of history presented in The Man in the High Castle, Phillip K. Dick, speculates what would have happened if the Axis powers won WWII.

Fantasy, on the other hand, tends to look back at pre-industrialized times or creates separate worlds altogether. Even when set in contemporary times, fantasy often incorporates elements from historical traditions or mythology.

You might find:

• 👑Medieval-style realms: Kingdoms, knights, and political intrigue are often crucial parts of fantasy novels. Example: George R. R. Martin sets the Game of Thrones series in the war-torn, politically complex world of Westeros and Essos.
• 🔮Mythical pasts: Many writers choose to craft stories on lost civilizations, with epic world-building that takes inspiration from folklore or legends. Example: In Circe, Madeline Miller reimagines Greek mythology through the life of Circe, an enchantress, blending myth with rich storytelling.
• 🗺️Fully invented worlds: Or, some might choose to create a new world entirely, completely disconnected from the Earth we know with its own unique geography, species, and cultures. Example: In The Priory of the Orange Tree, Samantha Shannon presents a complex, original fantasy world split into the East, West, and South. Each sector boasts its own unique culture based on their attitudes towards dragons and conflicting legends in their stories on how an evil dragon known as the “Nameless One” was defeated.

Though vastly different, each time and location brings a different flavor to these immersive stories. However, as we’ll see in my next point, these worlds aren’t just backdrops, but powerful vessels for carrying important themes and deeper meaning.

Thematic approaches

To break it down on a more molecular level, here’s a handy table with some of the themes you can expect to find in each of these diverse genres:

Now that we’ve unpacked the key themes driving each genre, let’s dive into the classic tropes and aesthetics that keep fans coming back for more…

Tropes and aesthetics

Just as you probably won’t find a mad scientist in a fantasy epic, you also won’t stumble across a dragon rider in a science fiction novel. 

That’s because each genre comes with its own tropes and aesthetics. Science fiction thrives on pushing the boundaries, so you’ll find lots of mind-bending time travel, technological utopias, apocalyptic dystopias, and experiments gone horribly wrong. One of its most enduring tropes — the mad scientist unleashing a terrifying creation — can be traced back to Mary Shelley’s Frankenstein, often hailed as the first science fiction novel. Their worlds also come with sleek futuristic visuals: gleaming skyscrapers, for instance, and a color palette dominated by whites, electric blues, and neon lights. 

By contrast, fantasy usually embraces earthy, organic tones, drawing heavily from history to erect landscapes full of crumbling castles and secret forests. Trope-wise, it calls upon archetypes like quests for “MacGuffins” (an object vital to the plot, but insignificant in itself), along with age-old curses and prophecies that shape characters’ fates. You’ll probably often spot “the chosen one” who’s destined to change the world — like in Rick Riordan’s Percy Jackson series, where our protagonist Percy must accept his destiny as the son of a Greek god. 

Reader expectations and subjectivity

Over the many years that science fiction and fantasy have existed in literature, films, and art, fans of the genre have naturally developed a set of expectations. Though both science fiction and fantasy novels typically range between word counts of 80k to 150k, it’s known that subgenres of fantasy, like high fantasy, often exceed the 150k mark and are more likely to be part of longer, multi-book series compared to science fiction.

Whilst these expectations are cues that help readers find books suited to their tastes, sometimes they can be more misleading than helpful. Publishers often choose to market a book strategically by stretching genre boundaries to appeal to broader audiences. While this can be more irritating for diehard fans, it points to a larger conclusion: rigid categorization isn't always necessary or helpful. Cue hybrid genres.

📖Hybrid genres

On the subjectivity of genre, renowned author Ursula Le Guin wrote: 

 “But of course fantasy and science fiction are different, just as red and blue are different; they have different frequencies; if you mix them (on paper—I work on paper) you get purple, something else again.”

Many now hold a similar view to Le Guin, preferring to see science fiction and fantasy not as separate boxes but points on a spectrum of speculative fiction, with the hybrid genre “Science Fantasy” at their intersection. Here are a few examples of “Science Fantasy” to better illustrate this blend:  

📚Star Wars: With its galactic backdrop, high-tech gadgets, and melodramatic storylines, the series certainly meets the criteria of a science fiction space opera. However, with elements of Jedi mysticism like “The Force”, fans can’t deny that it also satisfies the requirements of fantasy. Here, it is accepted that both genres can coexist harmoniously.

📚Mistborn: Likewise, fantasy worlds can include scientific rigor with hard magic systems, as established by previously mentioned author Brandon Sanderson. In his own trilogy, Mistborn, the magic system “Allomancy” is presented as a scientific discipline where characters burn certain metals to gain supernatural powers such as emotional manipulation or heightened senses. These rules set an expectation for readers that helps them get to grips with exactly what a character is capable of, without sacrificing any elements of fantasy or wonder. 

So, rather than viewing genres for their differences, the success of these hybrid examples prove that it's much more exciting for readers, authors, and publishers alike to picture genre as a sliding scale. In this case, at one end we have pure hard science fiction, high-fantasy epic at the other, and a wide middle where science and sorcery intermingle.

By embracing elements from both genres, authors unlock a whole new world of possibilities — where technology and magic enrich each other. This new approach also ensures that both science fiction and fantasy can continue to evolve and mesmerize new generations of fans to come.

Whether you prefer the technological speculation of science fiction, the magical wonders of fantasy, or works that blend elements of both, these genres offer rich storytelling possibilities that continue to captivate audiences worldwide. 

So, if you're picking up your next book, or looking to write your own science fiction or fantasy novel, get ready to dive into the extraordinary — whichever path you choose.