How to self-publish a fantasy or sci-fi novel
Fantasy and sci-fi run long, signal genre hard on the cover, and often launch as series — so they need different decisions on word count, trim size, maps and formatting. Here is the genre-specific playbook, with a norms table.
To self-publish a fantasy or sci-fi novel you follow the same seven stages as any book — edit, design, format, ISBN, distribute, launch — but four things change: your manuscript runs long (epic fantasy commonly 100,000–150,000+ words), your cover must shout genre at thumbnail size, you will likely want a map or interior art, and you should plan as a series from book one. Everything else is shared craft.
This guide covers only what is different for the genre. For the full path, see how to self-publish a book and come back here for the fantasy-and-sci-fi specifics.
How long should a fantasy or sci-fi novel be?
Longer than almost any other genre, and readers expect it. A standalone fantasy typically runs 90,000–120,000 words; epic and high fantasy routinely push past 150,000. Science fiction is a touch leaner — roughly 90,000–125,000 — because it leans on idea and concept rather than sprawling worldbuilding, though hard SF and space opera happily run longer. These are guides, not rules: they reflect what agents, publishers and genre readers have come to expect, as set out in current word-count guidance from the Manuscript Academy.
The self-publishing freedom is real: no gatekeeper will reject you for length. But length is not free. Every extra 10,000 words adds pages, and pages add print cost and reader commitment. A debut that runs to 200,000 words signals unedited more often than epic. If your draft is enormous, the answer is usually a structural edit, not a bigger trim size — and sometimes the honest move is to split it into two books.
Why does the cover have to signal genre so hard?
Because fantasy and sci-fi readers shop by visual code, and they decide in a glance. A reader scrolling a retailer category has been trained over decades: gilded title, atmospheric landscape and a lone figure reads epic fantasy; chrome typography, a planet and hard geometry reads science fiction; a moody figure with a glowing rune reads romantasy. Get the code wrong and the right reader scrolls straight past, however good the book is.
This is the genre where an AI-generated cover hurts most. SF and fantasy fans are the most format-conscious, image-literate audience in publishing, and they spot the averaged AI look instantly — melting hands, uncanny armour, warped lettering on a title. We draw and illustrate every cover by hand, never with AI, precisely so it can carry the specific subgenre signal your book needs and hold up against the traditionally published titles sitting next to it. If you want the wider logic on AI versus a person, see how much a book cover costs and what that fee actually buys.
Do I need a map or interior illustration?
Often, yes — and it is one of the genre’s real pleasures. A map in the front matter is close to expected in secondary-world fantasy; readers flip back to it constantly, and its absence can read as a missing piece. Sci-fi leans on different art: a system chart, a ship schematic, a faction sigil, a timeline. Beyond the map, fantasy and sci-fi welcome decorative chapter openers, ornamental scene breaks and the occasional full-page illustration in a way literary fiction does not.
The craft detail that trips people up is resolution. A map that looks crisp on screen will print as a grey smudge if it is not built for it: interior line art needs to be at least 300 DPI at its final printed size, in greyscale, with lines heavy enough to survive the press. We handle maps, sigils and chapter art as part of illustration — drawn to your world, supplied at print resolution and matched to the cover so the whole book feels of a piece. Standalone illustration starts from 10 EUR.
What trim size suits a long genre novel?
Here is where instinct misleads first-time authors. The obvious move for a long book is the larger 6″ × 9″ trim, because it packs more words per page and keeps the page count — and the print cost — down. But genre-fiction readers have been conditioned by decades of mass-market and trade paperbacks in the narrower 5″–5.5″ range. Pick up a 6″ × 9″ novel and it feels like a textbook, not a story.
The genre standard for fantasy and sci-fi paperbacks is 5.5″ × 8.5″. It reads as fiction, sits right in the hand, and matches the shelf. The cost you pay is page count: a 120,000-word novel that runs around 320–360 pages at 6″ × 9″ will run roughly 380–420 pages at 5.5″ × 8.5″, per Cambric’s fantasy formatting guide. For a long series that adds up, so weigh reader expectation against print economics. Our full walkthrough of the trade-offs is in how to choose a trim size for your book.
One hard limit to know before you commit: Amazon KDP caps a black-and-white paperback at 828 pages and a hardcover at 550 pages, per KDP’s paperback submission guidelines. A genuinely vast epic at 5.5″ × 8.5″ can bump the hardcover ceiling — another reason to size the trim and the edit together. These limits are set by the retailer and can change, so confirm the live figures in your KDP dashboard.
Fantasy and sci-fi: the genre norms at a glance
| Decision | Fantasy | Science fiction | Why it differs |
|---|---|---|---|
| Standalone word count | 90,000–120,000 | 90,000–125,000 | Worldbuilding needs room; SF leans on concept |
| Epic / long-form | 150,000+ common | 120,000+ for space opera, hard SF | Reader expectation, not a rule |
| Standard paperback trim | 5.5″ × 8.5″ | 5.5″ × 8.5″ | Reads as fiction, not a textbook |
| Cover signal | Atmosphere, gilt title, lone figure | Hardware, planets, chrome type | Readers shop by visual subgenre code |
| Interior art | Map almost expected | System chart, schematic, sigil | Secondary worlds need orientation |
| Structure | Often a series / trilogy | Often a series or shared universe | Read-through drives the genre |
| Body font | Serif (e.g. Garamond, 11pt) | Serif; restrained sans for SF feel | Long reads demand legibility |
How do I set up a series from book one?
Fantasy and sci-fi live and die by the series, so build for it before book one is even on sale. Three things to lock early. First, visual identity: the title typeface, the layout grid, the spine treatment and the art style should be a template, not a one-off, so book three is unmistakably the same shelf as book one. Keeping the editable source files matters here — you reuse them, you do not rebuild. Second, naming and metadata: register a series name, number the books clearly, and keep your categories and keywords consistent so retailers link the titles and feed read-through.
Third, understand the economics that reward series. Many genre authors enrol in Kindle Unlimited, where you are paid per page read rather than per sale — a rate that hovers around $0.0045–$0.005 per page and shifts monthly with the global fund, per Written Word Media’s payout tracker. A reader who devours your whole series in KU can be worth more than a couple of single sales, which is why series with strong read-through dominate the genre’s KU charts. That rate is set by Amazon and shifts month to month — a volatile figure to verify live before you price.
What is different about formatting a long book?
Length changes the interior craft. With 400-plus pages you must be ruthless about legibility: a clean serif body face at a comfortable size, generous line spacing, and running heads so a reader who surfaces at 2 a.m. knows where they are. Chapter openers and scene breaks do real navigational work across a doorstopper, not just decoration. Front and back matter carry weight too — a map up front, and often a glossary, dramatis personae or appendix at the back for a cast and world this large.
On the digital side, every one of those elements has to survive reflow. A fixed map must scale on a phone screen, internal links to a glossary should actually jump, and the ePUB has to validate. We build an EPUBCheck-validated reflowable ePUB 3 and a press-ready interior in the same pass, both made to pass KDP, IngramSpark and every store the first time. You keep all rights and the editable source files, so the next book in the series starts from your own template, not a blank page.
Where Librum fits
Fantasy and sci-fi ask more of a book than most genres — the length, the map, the cover that has to win a thumbnail fight, the series that has to look like a series. If you would rather hand the production to people who have done it for fifteen years, we draw your cover and map by hand, build files that pass first time, and give you a fixed quote up front, usually within a day. See our illustration service for the map and chapter art, or send us the manuscript and we will come back with a plan, a price and a timeline.
Frequently asked questions
How long should my fantasy or sci-fi novel be?+
A standalone fantasy usually runs 90,000 to 120,000 words, and epic fantasy often passes 150,000. Science fiction sits around 90,000 to 125,000, leaning on concept over sprawl. These are reader and industry guides, not rules. Self-publishing removes the gatekeeper, but an over-long debut tends to signal under-editing rather than epic ambition.
What trim size should I use for a long genre novel?+
The genre standard is 5.5 by 8.5 inches. It is tempting to choose the larger 6 by 9 to save pages and print cost, but genre readers expect the narrower trim and a 6 by 9 novel reads like a textbook. The trade-off is page count: the same book runs longer at 5.5 by 8.5, so weigh reader expectation against print economics.
Do I really need a map in my fantasy novel?+
Not strictly, but secondary-world fantasy readers often expect one and flip back to it constantly. Sci-fi leans on different art, such as system charts or ship schematics. Whatever you include, build interior line art at 300 DPI or more at final printed size, in greyscale, or it will print as a grey smudge rather than crisp lines.
Should I plan my book as a series from the start?+
Yes. Fantasy and sci-fi are driven by series read-through, so lock your visual identity, series name and metadata at book one. Keep the editable source files so later books reuse the template rather than rebuilding it. If you enrol in Kindle Unlimited, a reader who finishes the whole series can earn you more than a couple of single sales.