In April 2021, users of AI Dungeon, the wildly popular AI text adventure game, discovered something unsettling. The company behind it, Latitude, had been letting human moderators read players’ private, unpublished stories without telling anyone.
These weren’t public posts. They were personal creative fiction, sometimes deeply private, written by people who assumed nobody was looking. Latitude had also rolled out new content filters that were so aggressive they’d flag innocent phrases while breaking gameplay for rule-following users. The Google Play rating cratered from 4.8 to 2.6 in weeks.
The trust was gone. And a small group of people from that community decided to build something different.
A Tool Born from Betrayal
NovelAI launched on April 28, 2021, right in the middle of the AI Dungeon meltdown. The team behind it, a company called Anlatan, wasn’t a well-funded startup with a pitch deck and a growth strategy. They were users. Writers, developers, and AI enthusiasts who’d been part of the AI Dungeon community and watched it implode over the exact issues they cared about most: privacy and creative freedom.
Anlatan is a small, fully remote team spread across the globe. Eren (known online as Kurumuz) serves as CEO and Head of Research, leading the AI model development. Virginia (Aini), a German artist with a decade of experience in gaming and community management, runs project management. The rest of the team covers backend development, frontend work, infrastructure, and a role you don’t see at most startups: “datasetting,” the careful curation of training data for fiction-specific AI models.
They built NovelAI on two principles that came directly from watching AI Dungeon burn down. First, your stories should be encrypted so that even the people running the platform can’t read them. Second, an AI writing sandbox should not tell fiction writers what they’re allowed to imagine.
Five years later, those principles still define everything about the tool.
What NovelAI Actually Does
Strip away the origin story and NovelAI is a generative co-writing tool. You write prose, the AI continues it. You steer it with context, settings, and a Lorebook system (their version of a story bible), and the AI picks up where you leave off, matching the tone and direction you’ve established.
It also has a Text Adventure mode where you give commands and the AI narrates what happens, like a choose-your-own-adventure engine running on a language model trained specifically for storytelling.
What it is not: a grammar checker, an outlining tool, an editor, or a manuscript management system. It doesn’t offer plot structure templates or character arc tracking. If you want a polished writing suite that holds your hand through the process, NovelAI will confuse and frustrate you.
This is a sandbox. A playground for prose. You bring the story; it brings the generative muscle.
They Train Their Own Models (and That Matters More Than You Think)
Most AI writing tools are, at their core, wrappers around someone else’s language model. They connect to OpenAI’s GPT or Anthropic’s Claude, add a nice interface on top, and call it a product. There’s nothing wrong with that approach, but it means every tool using the same model produces fundamentally similar output.
NovelAI does something different. They train and fine-tune their own models, built on a proprietary dataset they call Nerdstash. These models exist for one purpose: generating fiction.
Their current flagship, GLM-4.6 (released October 2025), is a 355-billion-parameter model with a context window that can hold roughly 28,000 tokens of your story in memory at once, with an additional 8,000 tokens of rollover. Below that sits Erato, a 70-billion-parameter model based on Meta’s Llama 3, further trained on hundreds of billions of tokens of fiction-focused data. For users on the entry-level Tablet plan, there’s Kayra, a capable 13-billion-parameter model built entirely in-house.
Why does this matter for you as a writer? Because a model trained specifically on fiction understands narrative differently than a general-purpose chatbot. Pacing, voice, dialogue rhythm, the way a scene builds tension before a reveal: these are things a fiction-tuned model handles with more nuance than a model designed to also write marketing emails and answer trivia questions.
The tradeoff is that NovelAI can’t tap into the latest GPT or Claude model the way a BYOK tool can. You’re committed to Anlatan’s models. When they’re good (and Erato and GLM-4.6 are genuinely good), this is a strength. When a competitor releases something remarkable, you’re waiting for Anlatan to catch up.
Encryption You Can Actually Trust
Remember the AI Dungeon disaster? NovelAI’s answer to that isn’t a privacy policy. It’s math.
Every story you write is encrypted in your browser using XSalsa20 (a stream cipher) before it ever reaches NovelAI’s servers. The encryption key is derived from your password through argon2 hashing. What this means in practice: the stories stored on NovelAI’s servers are scrambled data that even Anlatan’s own staff cannot read.
During active generation, unencrypted portions of your story do travel to their servers so the AI can process them, but that data is transmitted over HTTPS and isn’t logged or stored.
This design has a real consequence. If you forget your password and reset it, your stories are gone. There’s no recovery, no “contact support” option. The encryption is genuine, and genuine encryption means nobody has a back door, not even the people who built it.
For writers working on sensitive material, or simply writers who believe their creative work is nobody’s business but their own, this level of privacy is rare in the AI writing space.
The Lorebook: Teaching the AI Your World
NovelAI’s Lorebook is how you give the AI persistent memory about your story. You create entries for characters, locations, rules of your world, plot details, and anything else you want the AI to remember. When certain keywords appear in the text, the relevant Lorebook entries get pulled into the AI’s context window automatically.
It’s a simpler system than what you’d find in a tool like NovelCrafter (which builds an entire structured database around your story world). The Lorebook is more like a set of reference cards the AI can peek at when it needs them. For writers who prefer a lighter touch, this works well. For writers managing epic fantasy series with dozens of named characters and interconnected plotlines, it may feel limited.
The Image Generation Side
NovelAI also generates images, and they’re quite good if you’re into anime-style art. The platform produces roughly 4.8 million images per day across its user base, which tells you something about how popular this feature is.
The image generation runs on NovelAI’s own custom diffusion models, with tools for inpainting, upscaling, and a “vibe transfer” feature that lets you guide the style of generated images. It’s focused squarely on anime and manga aesthetics. If you want photorealistic cover art or watercolor illustrations, this isn’t the tool.
For fiction writers, the practical use case is concept art: character visualizations, scene compositions, cover mockups. It’s a nice bonus bundled into a writing subscription rather than a standalone product you’d pay for separately.
Who This Is For (and Who It Isn’t)
NovelAI rewards a specific kind of writer: someone who enjoys tinkering with tools, who doesn’t mind spending time adjusting parameters to dial in the output they want, and who values creative freedom and privacy above guided workflows.
It has a real learning curve. The interface offers sampling parameters, context settings, prompt engineering options, and configuration choices that can feel overwhelming if you’re coming from a simpler tool. Getting consistently good prose output requires understanding how the models work and investing time in your Lorebook. This is not a “type a prompt and get a chapter” experience.
NovelAI is a good fit if you:
- Write fiction and want AI that was trained specifically for fiction
- Care about privacy and want real encryption, not just a policy document
- Enjoy a sandbox approach where you control the generation process
- Want AI, image generation, and text-to-speech in one subscription
- Are comfortable with a tool that has knobs to turn and settings to learn
NovelAI is probably not for you if you:
- Want an all-in-one writing suite with outlining, editing, and structure tools
- Need your AI writing assistant to work out of the box with minimal setup
- Write primarily nonfiction, marketing copy, or business content
- Want to choose your own AI model (NovelAI uses only its own models)
- Prefer a polished, guided experience over a flexible sandbox
The Bottom Line
NovelAI exists because a group of writers and developers decided that AI creative tools should respect two things: your privacy and your imagination. That origin story isn’t just marketing. It’s baked into the technical architecture (real encryption) and the product philosophy (no content filters on fiction).
The tool that grew from those principles is genuinely unique. It trains its own fiction-specific models, encrypts your stories so nobody, not even the team running the platform, can read them, and wraps it all in a subscription that also includes anime-style image generation and text-to-speech.
It is not the easiest AI writing tool to learn. It doesn’t hold your hand. It won’t outline your novel or check your grammar or walk you through a three-act structure.
But if you’re a fiction writer who wants a powerful, private, creative sandbox where the AI was purpose-built for storytelling, NovelAI is one of the only tools in this space that can honestly make that claim.
