Does NovelAI Have a Filter? Price, Models, and Alternatives

NovelAI is the elder statesman of AI fiction. It was built in 2021 by people fleeing the AI Dungeon filter fiasco, and it earned trust the hard way: no content filter, unlimited generations at a flat price, and client-side encryption so the company cannot read your stories. That last part is still rare in this space, and it's genuinely to their credit.

We're not going to pretend NovelAI is bad. It's a serious product with a loyal community and five years of consistent policy behind it. What we will do is explain what changed over the last year, and who each tool serves now.

What changed at NovelAI

For years, NovelAI trained its own storytelling models. That era ended. In October 2025 they moved every tier to GLM-4.6 — a strong open-weights model — and in March 2026 shipped Xialong, their own finetune of it, exclusive to the $25 Opus tier. It was a reasonable engineering call: keeping pace with frontier labs on your own GPUs stopped being possible.

But it defines the ceiling. NovelAI's best model is a finetune of an open-weights model. It does not offer Claude, Gemini, or Grok at any price. If you've read prose from a frontier model recently, you know that gap is real — the pacing, the subtext, the sentence-level choices. It's the difference you feel ten turns in, when the scene either deepens or starts repeating itself.

Flat subscription vs pay-as-you-go

NovelAI's pricing is honest and simple: $10, $15, or $25 a month, unlimited text generation. If you write for hours every single day, that math is hard to beat, and we won't pretend otherwise.

Underfiction is pay-as-you-go. You buy credits, you spend them on the words you generate, and they never expire. If you write a few evenings a week, you'll likely spend less than a subscription. If you write heavily every day, you may spend more — but you're spending it on frontier models that no subscription anywhere will sell you for fiction.

Privacy, honestly compared

NovelAI encrypts stories client-side, which means their servers hold ciphertext they cannot open. For stored stories, that is the stronger guarantee, full stop.

Underfiction takes a different route: stories, characters, and worlds live on your device and sync between your devices encrypted at rest, and we don't read them. Portable archives let you take one story or the complete library with you. On top of that, inference runs through providers that separate your account identity from your prompts before they reach a model. Different architectures, same instinct. Both are miles ahead of platforms that keep your fiction in plaintext next to your email address.

So which one?

If you write many hours a day, want anime image generation, or client-side-encrypted cloud storage is your deciding factor — NovelAI remains a good product, and switching would gain you little.

If prose quality is the point — if you want the models that currently write the best fiction, inside a tool that manages scene memory for you — that's what Underfiction is for. Import your lorebooks and characters as world books and TavernCards and see whether the difference reads as clearly to you as it does to us.

Other NovelAI alternatives worth knowing

NovelAI doesn't lose users the way Character.AI does. Nobody storms out over a filter, because there isn't one. People look elsewhere for two quieter reasons: the model ceiling, which you feel a few scenes deep when the story either opens up or begins to repeat itself, and the arithmetic of a flat subscription for someone who writes three evenings a week. If Underfiction isn't the shape you want, these are the others we'd point you at.

Sudowrite is for writing a novel you intend to finish and sell: outline tools, scene expansion, a Story Engine that drafts alongside you. Plans run $10 to $44 a month billed annually, differing only in monthly credit pools. It is not interactive fiction and doesn't pretend to be — you are the author at a desk, not a character in the scene.

Novelcrafter charges $4 to $20 a month for the writing environment — codex, planning boards, chapter structure — and you connect your own model key and pay the provider directly. The codex will feel familiar to any lorebook user. Nothing is bundled: model choice, cost control, and refusal behavior are all yours to manage.

SillyTavern is free, open source, self-hosted, and pointable at anything, including a model on your own hardware — the one configuration nobody can ever change underneath you. Lorebooks, group scenes, total prompt control. The cost is your time: it's software you administer, not an app you open.

AI Dungeon is the purpose-built version of text adventuring: scenarios, quests, a game economy. Free to start, then $14.99 to $99.99 a month. Solo play is close to unfiltered, and the prose keeps a game register — event-driven, second person — which is either the point or the dealbreaker.

When staying with NovelAI is right, honestly: if you write many hours a day, flat-rate unlimited generation is arithmetic nobody here beats. If client-side encryption is your deciding factor — the company cannot read your stories, full stop — NovelAI remains nearly alone in offering it; Underfiction syncs stories encrypted at rest and we don't read them, but the key model is not client-side. And if anime image generation matters to you, that's still their crown jewel.

Underfiction is interactive storytelling under your direction. Your library is local and portable. New accounts start with 200 free credits.