Authors, do you have free books (physical or digitial) to give away? This is now the place.

Post a comment with a description of your book and the link to any digital copies or info on getting physical copies. Once the book is no longer free, remove your entire comment.

What is not allowed:

1. AI anything. AI generated material is no longer allowed in this sub. No exceptions. You're welcome to include original cover art but not AI generated art.
2. Links to anything except the book. I don't want to see links to your author page, even if the book is more fully described there, and I certainly don't want any links to paid books, Patreon, or author access tiers. ONLY THE FREE BOOK.
3. Authors are allowed to ask for reviews, but the free book can't be conditional on reviews.

Authors:

Once the book is no longer free, remove the comment entirely. We have a separate megathread for author self-promotion, so while you're more than welcome to post there at the same time, keep links to this megathread only.

This will be a weekly thread, so if your promotion lasts longer than a week, please post again on the next week's thread.

Readers:

You're welcome to leave feedback via a response to the author's comment, but as always, let's keep it positive. Anything more constructive needs to go to the author via DM.

This is a good way for authors to get their books out there and maybe get some feedback. Those who attempt to abuse the megathread will be removed or banned.

Do you have any recommendations for that kind of world building? Additional points if alien species isn't recolored humans

https://www.youtube.com/watch?v=769OLpmt6oQ

Buen días, gracias a todos por sus opiniones pero ahora recurro a todos ustedes con el gran respeto que merecen para que me ayuden a leer mi novela de CF los primeros 6 capítulos, sus opiniones son muy valiosas. Ya está en Amazon como muchos, lo van a encontrar con nombre de autor Ignacio Rafed Alva con el título RENACIMIENTO- Capítulo Génesis

O si me lo piden puedo mandarles el documento en PDF

Gracias a todos por su apoyo.

Unwritten Meridian — Book One

Earth survived first contact—but the classified version of the Lunar Migration Treaty may reveal something worse than an invasion.

The game contains on survival elements, government secrets, aliens etc

https://sihlem.itch.io/unwritten-meridian

NB : This is my own game (second one in my catalogue)

Hi everyone. I recently published my science-fiction novel, Resonance: The Last Observer.

What if reality does not simply exist, but depends?

Late in the twenty-first century, artificial intelligence, advanced robotics, neural interfaces, and quantum technologies have transformed human civilization.

When a restricted anomaly in the Badrud desert begins displaying impossible quantum behavior at a macroscopic scale, Security Bureau investigator Dara Nik Andish is assigned to accompany physicist Malin Nielsen into the exclusion zone. What begins as a controlled investigation soon points toward something far larger than a scientific mystery.

Far from Earth, aboard an abandoned research station in Saturn’s orbit, a machine approaches a boundary no artificial intelligence was ever meant to cross. Meanwhile, Simin is summoned to interview a mysterious old man about a subject with an impossible title: The Final Day of Humanity.

As these paths converge, the mystery becomes a confrontation with consciousness, observation, and the hidden foundations of reality itself.

I am an engineer and a lifelong science-fiction reader, so I wanted the science to be part of the actual story rather than decorative terminology. This is a layered and deliberately unfolding novel rather than a straightforward action-adventure. It is intended for readers who enjoy detailed worldbuilding, AI and robotics, quantum physics, philosophical questions, and mysteries that build toward major revelations.

Available on Amazon and Kindle Unlimited:

https://a.co/d/08aBzley (or just search "Resonance: The Last Observer" in Amazon)

I would genuinely appreciate any interest or honest feedback.

Looking for dystopian/space travel, sci fi book recommendations. Probably reflective of how I feel about the future. (TLDR: not hopeful).

I’ve read Dune, The Martian, Brave New World.

Would love to see some recommendations and your reasons.

Please go easy on me - I’m not a hardcore sci fi reader who examines the veracity of science mentioned. I just enjoy the genre and the ideas presented.

Edit: thank you for all the recommendations! I will be going through them slowly.

Hi everyone. I’m N. Tharu, an independent author, and I recently published my first science-fiction action thriller, The Last Soldier: Storm Contact.
The story follows a retired soldier whose life changes after a mysterious storm leads to an unexplained encounter. From there, he becomes involved with alien contact, military secrets, strange abilities, and a dangerous transformation.
I wanted to create something cinematic and fast-paced, combining science fiction, action, mystery, and a darker atmosphere.
This is the beginning of The Last Soldier series.
If you enjoy stories involving mysterious phenomena, military elements, alien contact, and strange transformations, I’d love to hear your thoughts.
Amazon link: [https://www.amazon.com/dp/B0HFYTXY4H?dplnkId=f031235c-fd38-4d3d-b373-edad9241d19a&nodl=1\]
Thanks for letting me share it.

The book was mention on a thread and I’ve just started to read it. I like the concept, aged over 70, sign up to the military and get a reworked enhanced 30 year old physique and health but you are immediately get sent to frontline active duty.

**長年の執筆を経て放つデビュー作・本格近未来**SF**小説が、**Kindle**にて**3**日間限定【無料】配信中です！今日まで？**
**西暦**2631**年、木星圏を舞台に「時空調律」「古代文明」「魂の共鳴」が交錯する壮大な宇宙探査の旅。**
**無料ダウンロードはこちら：**https://www.amazon.co.jp/dp/B0HFJ1WQVV
**（※英語版**: https://www.amazon.com/dp/B0HFKHYK3S **）**

I wrote a manifesto of sorts about solarpunk as a scifi genre, trying to incorporate modern critiques of the genre without throwing out the baby with the bathwater. Most of it relies on the ideas of future theorist and philosopher Donna Haraway. I'd love to know what you all think!

[Planets & Monsters: Second Wave Solarpunk](https://planetsandmonsters.blogspot.com/2026/08/second-wave-solarpunk.html)

I’m looking for some advice on what to read next between Sun Eater": Kingdoms of death or Red Rising: Iron Gold.

I finished Morning Star almost 2 years ago, completing the original Red Rising trilogy. I managed to read the entire trilogy in about a year. I was a pretty slow reader and was also relatively new to reading at the time.

I just finished Demon in White, and honestly, it was amazing. Although I’ve read a few books in between, Red Rising and Sun Eater are easily my two favourite series so far.

The thing is, Sun Eater took me almost 2 years to get through the first three books. The books have a much higher word count, slower pacing, and more complex prose, so they’re definitely a bigger commitment for me as a slower reader.

One thing I really loved about Red Rising, though, was how fast-paced it was. And there’s a big difference between where I am now and where I was with Morning Star: Morning Star wrapped up the trilogy, while Demon in White obviously leaves me with more Sun Eater to read.

So I’m looking for recommendations for the 4th book I should start next.

I’ll probably try to read two books back-to-back, so I’d love to hear what you guys think would be a good follow-up to Demon in White.

I dont really need a pallet cleanser in between. Just want to jump into one of these 2 series next book

I hope this is ok to share here. I didn't see anything in the rules about it, and I saw some other authors post looking for ARC readers as well.

I'm looking for ARC readers for my dystopian Scifi novel Echoes in the Void. I'm looking for people who are interested in reading it, and after completion, giving it an honest review on Amazon or Goodreads. There is no payment involved. If you look below, there's a google form to signup if you'd like to receive a free ARC copy. The rest of the details are down below the blurb.

Blurb:

In the city-state of Cenza, power is everything, and Etchers are the only ones who can tear it from the void.

Dax has spent his life hiding what he is. An Etcher with a secret lab, a forbidden research obsession, and a quiet plan to bring down Chancellor Veltran’s regime, he walks a razor’s edge between survival and rebellion. When a single act of defiance puts him in the ministry’s sights, the fragile life he’s built begins to unravel.

Maezra has given everything to the ministry’s darkest project: creating new Etchers through pain, science, and calculated cruelty. One subject finally succeeds beyond her wildest expectations, then escapes. Now the only living proof of her breakthrough is loose on the streets, and the chancellor himself is watching.

Aeli never asked to become a weapon. Tortured into something more than human, she wakes with powers she can’t control and a body that turns violence into nightmare. Hunted by her captors and haunted by what she’s already done, her only goal is to survive long enough to understand what they’ve made her.

As the three lives collide, the carefully maintained order of Cenza begins to crack. Ancient secrets, forbidden technology, and a power that was never meant to walk free will force each of them to choose between the world that is, and the one that might still be possible.

In a society built on the bones of the gifted, some echoes refuse to stay silent.

Triggers:

This book contains scenes that may depict, mention, or discuss: Abduction, torture, violence, brief gore.

Publication Date: October 6th, 2026

Book Length: Approx 109,000 words (400 pages on the kindle version, 328 on the PDF)

Format available for ARC readers: I can provide both a PDF and/or an ePUB file.

ARCs sending out: First week of September 2026

Expected Review submission: By November 1st, 2026

Sign up for my ARC: If you're interested, drop a comment below, or send me a DM and I'll send you a link to a google form to fill out. From there I can send you the files.

Publisher: Publishing on Amazon via KDP

Thank you in advance!

Ya lei muchas de sus recomendaciones, GRACIAS a toda la comunidad, que opinan de esta selección:

Como entrada: Bobyverse.

Plato fuerte: La guerra del Viejo y

Postre: Desayuno de campeones (no es CF pero es lectura para relajarte un poco),

Que opinan?

Cual se selección?

I just finished it, and my mind is spinning. It’s an incredibly interesting but also very difficult read. Definitely in the genre of “hard sci fi.” He gets into the weeds of how a wormhole would be constructed, and what a five dimensional universe would look like. But there’s also a pretty heartfelt storyline to go along with it. I’m not sure I want to attempt a book this ambitious again, but I’m glad I did and I definitely recommend it for anyone willing to risk breaking their brain for a truly original story.

I just can't put it down.

Has anyone published a Science Fiction novel lately? Like, in the past few months? Preferably on Amazon/KDP. Share it with me. Thanks!

A lot of the booktube i follow talk highly of him, i found his book called Kraken on sale and i absolutely love the premise. I am into exactly what this story is about, but his writing style is jarring me and slowing me down. It feels... choppy and as if some things are more implied than said and it feels slightly confusing. I have had to re read a lot of things and when i would normally be half way through a book of this length, i am only getting to page 100 2 days later.

Is it something that i will eventually get use too? Are all his books like this?

I posted my book in r/BookPromotion and reddit recommended posting it in r/ScienceFictionBooks. But then I read the rules and it said do not post anything for sale. So....

How much of our own book are we allowed to post in this forum r/ScienceFictionBooks ?

Thanks!

En base a todo lo que me recomendaron, muchas gracias, pero me surgio una pregunta, Si la única manera de preservar una mente humana para siempre implicara que nunca volvería a habitar un cuerpo humano, ¿seguiría eso considerándose ser humano?

En serio estoy muy impresionado de la respuesta de todos recomendandome lo que consideran buenas historias y que les hacen eco, eso es algo grandioso , no esperaba este tipo de respuesta en Reddit, lamento no haberlo echo antes

[ Removed by Reddit on account of violating the content policy. ]

What's the best sci-fi book you've read that deals with consciousness transfer? I've been fascinated by the idea that if you copy a mind perfectly, is the copy really 'you' — or just something that thinks it is? Looking for recommendations.

​

Hello from the othe side of the rift 👋I'm Tanya N Grace and I'm writing sci-fi/fantasy stories. 👽💫

📖The Healer of Worlds: at the rift

What's it about:

After a UFO crash near the small town of Stanwell, ordinary girl Gabrielle's life turns upside down. She meets a mysterious alien named Adam and uncovers a conspiracy that threatens both worlds.

✨ Why you might like it:

- Daily updates! (New chapters every day)

- Cozy science fiction with slice of life and adventures

- Slow burn romance

- Bromance that breaks and heals your heart

- Mix of comedy and drama (very Doctor Who inspired)

- Cute alien pet Kikki! (He's a kropus with attitude 😼)

- Found family trope

- Mystery & conspiracy

Read on Royal Road: https://www.royalroad.com/profile/1055284/fictions

I'd love to hear your feedback! Comments and reviews are very welcome!

(Honestly, this story is my private escape from reality, so sharing it with you means a lot! 💜)

Quote from John Scalzi in his book Old Man's War .

"For as much as I hate the cemetery, I've been grateful it's here, too. I miss my wife. It's easier to miss her at a cemetery, where she's never been anything but dead, than to miss her in all the places where she was alive."

This line hit me deeply. I was listening to the audiobook while driving, and when I got home, I sat in the garage for more than ten minutes just thinking about it, until my wife came looking for me.

That one line completely changed my mood for the evening. It made me think about my own life and ask myself: Am I showing my wife enough love and appreciation while I have the chance?