Are you a fan of science fiction in all of its many, many forms? How about free online comics? Some of the most exciting webcomics are based on science fiction themes or have speculative writing elements. Imagining worlds that are different in so many ways through tech and science is a hallmark of the genre, and these comics all present diverse and exciting visions.

Here are 15 fantastic sci-fi comics that you can read for free online.

 

15. Key to the Future’s Fate

Starting the list is Key to the Future’s Fate by Gage Lippolt, and it is unique among the comics on the list due to solarpunk themes. Solarpunk refers to an aesthetic that blends nature and technology, and the setting of Lippolt’s comic is a brilliant example of that as background to an exciting comic with funny characters.

Key to the Future’s Fate is about an arrogant teenager named Leon (who happens to be a cat) who is brought to the future by organizations he will later help found in an attempt to create a better world overall. Time displacement has its problems, and that, of course, brings up questions of potential paradoxes. Time travel is tricky to get right, and it is interesting how Lippolt approaches such a scenario while maintaining a comedic tone.

If you are looking for an all-ages sci-fi comedy comic with a brighter vibe than most, give Key to the Future’s Fate a try. The comic’s setting and general aesthetic differ from some standard dystopian or war-bound science fiction settings.

 

14. Thunderstar

If you prefer science fiction with a touch of fantasy, like Buck Rogers or Star Wars, Thunderstar by Ryan Light is an excellent comic to add to your reading list. The comic resembles old sci-fi serials and has stylistic elements that borrow heavily from 1930s classics and 1970s reimaginings. The comic’s heavily stylized art is also quite a treat, resulting in good fun and visually exciting updates.

The comic’s conceit is simple: “A goth girl space pilot and her excitable engineer race against time to save the pilot's boyfriend from being sacrificed to an evil cult.” Thunderstar comic has a breakneck, action-oriented pace and a fluid, cinematic quality that turns what might be an initially simple idea into a webcomic equivalent of a roller coaster.

Thunderstar is a comic that evokes some of the best elements of Star Wars and other sci-fi-fantasy space operas, with a quality production style. You can tell creator Ryan Light has some background in storyboarding, and the comic is all the better because of that.

 

13. Sluggy Freelance

Sluggy Freelance is a sci-fi webcomic with a significant reputation and is an elder statesman among the comics on the list. Created by Pete Abrams in 1997, this sci-fi webcomic is approaching nearly 30 years of existence, which is an incredible milestone.

It also helps that the comic is excellent. While it started as a gag-a-day, the comic would change over time to incorporate more long-form sci-fi storytelling. The sci-fi elements can range from plot-centric to subtle, but the main appeal is the characters and the chronicling of their lives. Everything from mad science to time travel is on the table, all anchored by a richly developed cast of characters.

Sluggy Freelance is more than just an excellent comic with science fiction elements. It is also a living history document and a foundational text in free, online comics. If you have time to kill, this nearly 26-year backlog is worth tackling.

 

12. Altarion Saga

Altarion Saga, a webcomic by Whiteshaix, a real-life tattoo artist, has some incredible art to complement an exciting sci-fi setting of aliens and adventure. The comic is also part of a larger story that spans other comics and concerns itself with other empires in the Milky Way Galaxy.

The main story of Altarion Saga concerns the aftermath of the death of Emperor Shaix and the power struggle that erupts in the void. However, a mercenary band may be able to save the day and restore order to a galaxy in freefall. Altarion Saga is quintessential space opera fun.

The disappointing news is that the comic has been on a hiatus. However, there is a ton to read between the core story and the spinoff material. Whether this becomes an unfinished classic has yet to be determined, a sad reality for many great webcomics.  Regardless, Altarion Saga and its spinoff material is a classic in the making.

 

11. Trying Human

The genre's versatility is one of the most exciting things about science fiction, including romance stories. Trying Human, by Emy Bitner, is a unique entry for how it deftly uses science fiction trappings to tell a compelling love story between different alien races.

The comic is also full of deep-cut and obscure references to real-life alien conspiracies and UFO theory, such as incorporating the concept of the Majestic 12. The comic also features two parallel narratives, weaving a story in the past and present and forming exciting connections between the two time periods. The first story follows the abduction of Rose, a human, and her burgeoning relationship with an alien named Hue. Meanwhile, the past narrative in 1947 involves some iconic UFO lore.

Between gorgeous artwork, heavily-researched UFO theory, and a compelling romance across species, Trying Human is among the most unique sci-fi webcomics and certainly one of the best.

 

10. Space Wasters

Sci-fi parodies are always a welcome distraction, especially when they go beyond poking fun at a genre and develop their own compelling stories. Star Trek is often a frequent target of parody and the foundational text of the webcomic Space Wasters by QuipperSnapper and Pixie Press.

Space Wasters follows a ship crew, not unlike that of the Starship Enterprise, who happen to be captained by a real jerk. However, when pirates capture the captain, the crew goes on the run, and trouble follows right behind them. From there, you have a comic featuring hilarious and funky aliens ineffectually making their way across the galaxy and getting into real trouble.

This affectionate parody of a sci-fi staple goes beyond poking fun at a classic and, in turn, creates a fascinating story. Space Wasters is a top-tier comic to add to your reading list and among the best in a list of sci-fi greats.

 

9. Puffer and Clarissa

Puffer and Clarissa is a comic that evokes a singular question: what if Waterworld was good? While the sci-fi setting of this comic isn’t as high-tech as some other examples on the list, it fits the sci-fi genre of speculating on a new type of world. James Nelson’s Puffer and Clarissa is a relatively more recent webcomic on the scene but has already drawn great acclaim.

The comic follows Puffer White, a teenager who lives on a warship. She is also a genius inventor, assisting her mother to take over the world. However, she becomes separated during a ship raid and finds herself an adventuring partner in Clarissa. The pair's adventures evoke great young adult literature and series like Avatar: The Last Airbender.

Puffer and Clarissa is a great, all-ages comic to introduce to younger readers while maintaining compelling storytelling for an adult audience. Overall, it is an excellent read for sci-fi comics fans and well worth a bookmark.

 

8. Cassiopeia Quinn

Cassiopeia Quinn is another relatively new webcomic, especially compared to some of the older titles on this list. Still, it has established itself as one of the best sci-fi webcomics. The creators of the comic, Gunwild and Psuedonym, have put together a stunning-looking sci-fi adventure with an exciting cast of characters and some fun storytelling.

The comic is a comedic space adventure following the titular Cassiopeia, a stunning-looking outlaw just as popular as she is infamous. She and her robot partner, Zeke, are on various space adventures and tangle with Officer Madison Vrax of the Prime Galactic Navy. There is plenty of space piracy to enjoy.

Cassiopeia Quinn is undoubtedly one of the best-looking sci-fi webcomics out there. However, it also presents a charming and comedic adventure story involving mismatched characters that is well worth your time as well.

 

7. Spacetrawler

Christopher Baldwin’s Spacetrawler is another sci-fi legacy comic well-regarded by creators and readers alike. The comic is just one of many stories by the prolific Baldwin, but it is also particularly beloved for the unique sci-fi vision of the setting. Plus, with over 400 pages of comics to enjoy, you’ll have plenty to catch up on.

The comic follows Nogg, Krep, and Gurf, aliens representing the freedom-fighting organization Interplant Amity. Their primary goal is to fight the slavery of a sentient species, and they recruit a group of humans in the fight. If you like galaxy-spanning intrigue and non-human characters, Spacetrawler is an excellent choice. The art style also evokes European comics as well.

Spacetrawler manages the tricky feat of balancing comedy and drama. While the overall series is more comedic, darker, more serious elements give the comic a particular depth, making it immensely rewarding to read. Be sure to give this one a try.

 

6. Galaxion

Fans of the work of Leiji Matsumoto, such as Starblazers and Galaxy Express 999, will find a lot to love about the webcomic Galaxion. The comic was originally a series of printed works by Tara Tallan, but around 2006, it transitioned to a webcomic archive. The author was even nominated for a Joe Shuster award for their work on Galaxion.

Galaxion is a science fiction adventure series with elements of romance in a grand, space opera style. The comic’s tone is also quite bright and optimistic overall, which can be a nice change of pace from darker stories associated with the genre. The story follows the crew of a survey ship, the Galaxion, fitted with an experimental engine. Naturally, complications arise.

You owe it to yourself to check out Galaxion. The comic’s soft, retro aesthetic is quite a pleasure to take in from panel to panel. This is especially true as the comic transitions from the original printed to full-color digital pages. 

 

5. Starslip

When developing a list of the best online sci-fi comics you can read for free, Kris Straub’s Starslip is always in discussion. Running for seven years, the comic impacted the sci-fi genre in webcomics thanks to Straub’s hilarious writing and the increasingly compelling story. Straub is no stranger to influential creations. He also created the iconic horror story Candle Cove and other projects.

The comic presents a unique cast of characters aboard a museum ship that uses a particular drive to slip between parallel universes. The comic would begin as an affectionate parody but quickly evolve over seven years into a far richer story.

Part of the joy of reading long-running webcomics is seeing the stories' growth and evolution. Straub’s initial version of Starslip was good and would have made it to a best sci-fi comic list, regardless. However, the complexity of the later years of the comic put it above and beyond the genre.

 

4. Schlock Mercenary

Howard Tayler’s Schlock Mercenary is another example of a classic of the webcomic scene. This sci-fi comedy has been around since 2000 and finally finished its run around 2020. The series resulted in five Hugo Award nominations.

Schlock Mercenary follows the adventures of a mercenary company in a dystopian 31st-century space opera. Captain Kaff Tagon’s crew is involved in all crises, ranging from intergalactic wars to apocalyptic adventures. Also of note is how much storytelling is driven by the growth of technology in the setting and its unintended consequences.

Schlock Mercenary is a true sci-fi classic and one of the best webcomics. Few webcomics match its legacy, which has been covered by publications such as Wired, Ars Technica, and Analog Science Fiction and Fact.

 

3. Outsider

Very few sci-fi comics are as technical detailed in their world-building as Jim Francis’ Outsider. Though slightly infamous for a notoriously slow update schedule, the quality of every update and attention to detail quickly remind you why this is among the best sci-fi webcomics.

Outsider is a space opera comic with a more complex, more technical edge. The comic heavily focuses on starship combat and follows a young human officer participating in a galactic war on the side of the elf-like Loroi. However, the real stars of the comic tend to be the ship designs.

Outsider is an excellent sci-fi comic that has been running for quite a while. Though updates aren’t frequent, the ongoing story has a ton of entertainment to deliver.

 

2. Narbonic

Award-winning sci-fi author Shaenon K Garrity’s daily webcomic, Narbonic, ran from 2000 to 2006. The comic was relaunched in 2007 as a special director’s cut edition. The comic is in typical four-panel strip form, but the material has an interesting sci-fi twist.

The comic is an ensemble comedy revolving around characters affiliated with Narbonic Labs, the domain of mad scientist Helen Narbon. Some strips revolve around developing specific characters like Dave Davenport, a computer programmer, or Artie, a super-intelligent gerbil.

The director’s cut presentation of the classic webcomic is fascinating, thanks to Garrity’s extended commentary for each strip. The commentary is insightful and reveals depths of Narbonic that are delightful to discover.

 

1. Terra

Terra stands out among the best sci-fi webcomics at nearly 500 pages of exquisitely illustrated science-fiction action and drama. A story that looks this good, with such a compelling story, is an excellent fit for any publisher, but we’re lucky to have it available to read for free. Terra is the creation of husband-and-wife team Holly Laing and Drew Dailey.

The plot of Terra revolves around a group of guerillas working together to end a way between Earth and Azatoth. The war has pulled in various species and has galactic-spanning consequences. Laing and Dailey completed the comic in 2023, but it is set to be reimagined in a form called Terra Incognita, which will also be free to read.

Even with the upcoming re-imagining of the story, the original Terra is worth adding to your library of free sci-fi comics. The 13-year run of original pages is still fantastic, and the promise of a new take on the material is also exhilarating.

 

Even More Free Online Sci-Fi Comics

There are far more sci-fi comics out there than this initial list. Looking for even more sci-fi webcomics? Try Android Blues, Crimson Stars, To Wander, or Cosmic Dash. Or, check out websites like Tapas, Webtoon, and The Duck Webcomics to see what sci-fi titles are available. There is no shortage of fun sci-fi worlds to explore for free with online comics.