r/sciencefiction is a subreddit with 307k members. The most common kinds of discussions are advice requests and ideas, and the community frequently discusses sci fi, scifi, books, series, and book, and they frequently recommend/review sci-fi books, science fiction books, and science fiction.
This reddit is for fans and creators of Science Fiction and related media in any form. SF topics should involve plausible ideas reached through the rational application of science. General speculative fiction posts are fine as long as they primarily focus on Science Fiction.
Popular Themes in r/sciencefiction
#1
Advice Requests
: "I found the concept proposed by the theory that Earth is larger than we know quite entertaining. It's a silly idea, but it made me wonder if there are any books that explore similar themes. Can you recommend any?"
19 posts
#2
Ideas
: "I sculpted a xenomorph bc it's too expensive to buy a model of one these days"
2 posts
Popular Topics in r/sciencefiction
#1
Sci Fi
: "Help. Looking for old Sci Fi movie"
156 posts
#2
Scifi
: "Custom Scifi Laser Rifle Mk III with bare alu sheets by request. It holds various LEDs, meters and a working laser. I am not a fan of unpainted alu, personally. What do you guys think? Yay or nay?"
53 posts
#3
Books
: "8 sci-fi Books I will always recommend"
41 posts
#4
Series
: "In 1969, the BBC adapted Asimov’s novel ‘The Naked Sun’ as a 50-minute episode for its anthology Series ‘Out of the Unknown’. Later, in the mid-70s, the episode was wiped from the BBC archive"
35 posts
#5
Book
: "Totally real Book covers for you to read"
29 posts
#6
Fiction
: "[Promotion] The Wanderer: Hard Science Fiction from the Darkest Ocean"
26 posts
#7
Space
: "Dark Star (1974) is such a humorous, yet cynical depiction of humans in Space"
22 posts
#8
Science Fiction
: "Diaspora Greg Egan"
19 posts
#9
Worst
15 posts
#10
Story
15 posts
Products Discussed in r/sciencefiction
Sci-fi Books
150 reviews
#1
Robert A. Heinlein
4.6★ from 14 reviews
#2
Isaac Asimov
4.8★ from 9 reviews
#3
Orson Scott Card
5.0★ from 8 reviews
Science Fiction Books
102 reviews
#1
Arthur C. Clarke
5.0★ from 5 reviews
#2
Frank Herbert
5.0★ from 4 reviews
#3
Andy Weir
5.0★ from 4 reviews
Science Fiction
51 reviews
#1
Martha Wells
5.0★ from 4 reviews
#2
Andy Weir
4.7★ from 3 reviews
#3
Adrian Tchaikovsky
5.0★ from 3 reviews
Member Growth in r/sciencefiction
Yearly
+36k members(13.4%)
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About
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This page gives a focused view of r/sciencefiction, including current member size, discussion patterns, product reviews, and related communities to explore.
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Last updated: June 15, 2026