A Sudowrite Alternative, for Writers Who Want to Keep the Folder.
Sudowrite is the best-known AI tool for fiction, and generating prose is what it does best. Shiro is a book-writing app that keeps your manuscript in Markdown files on your computer and lets you choose the AI, a local one, your own key, or none. If you came for the sentences, start with Sudowrite. If you came for the book as a whole, read on.
| Shiro | Sudowrite | |
|---|---|---|
| Price | Free on your computer. Cloud is optional, see the pricing page. | Subscription with monthly credits. Hobby & Student is $10 a month billed yearly, or $19 billed month to month. Billed yearly, Professional is $22 a month and Max $44. Free trial, no card. |
| Platforms | Mac, Windows, Linux, and a web app for cloud projects. No phone app yet. | Web, and a mobile app described on its blog. The pages we read don’t name which phones. |
| Where your book lives | Plain Markdown files in a folder on your disk, or Shiro Cloud if you move a project there | Not stated on their site. Projects are shared between sessions, so we assume its servers. |
| Works offline | Yes, with no account | Not stated on their site |
| Role of AI | Optional. Can be turned off. | The core of the product |
| Models | Whatever you connect: a local model, your own key, or hosted on a Cloud plan | Dozens, including Claude, OpenAI models, open-source models and its own fiction model, Muse |
| Own key or local models | Yes, both | Not stated on their site |
| Trains on your writing | Shiro never does. With a key or hosted AI, the model provider’s terms apply too. | No, according to its FAQ |
| Export | EPUB, PDF, Word, Markdown, HTML, plain text, with Kindle presets and a pre-upload checklist | Word, a .zip of a project, .csv for Story Bible sections. Its export guide doesn’t mention EPUB or print PDF. |
Checked on the makers’ own websites in November 2026. Prices are in US dollars and change; tell us if we’ve fallen behind.
Choose Sudowrite If
- You want an AI to carry much of a first draft, and you want it working today with no models or keys to think about.
- You want a model made for fiction instead of choosing among general-purpose ones.
- You draft on your phone as well as your laptop. Shiro has no phone app yet.
- You’re happy planning and formatting elsewhere, and want one sharp tool for producing prose.
Choose Shiro If
- You want your manuscript as files on your own disk, readable with no app at all.
- You want to pick the AI: a model on your laptop, your own key, or none.
- You want the plan, the world and the finished EPUB and print PDF in the same project as the draft.
- You want to see exactly what each model was sent, and to keep some scenes away from all of them.
Two Apps That Start From Opposite Ends
Sudowrite starts with the model. It offers dozens of them, including Claude, OpenAI’s models, open-source ones and Muse, a fiction model it built itself, and its Story Bible holds your characters, world and outline so the AI has something to remember. There is nothing to install and no key to go looking for. You open it and ask for prose.
Shiro starts with the book. You get a folder on your computer and an app for planning, drafting, keeping track of your world and publishing the result. The AI is one room in that house, and the door has a lock.
What Happens to Your Files
A Shiro project is a folder of Markdown files, with names like 14 The Ferry.md. The desktop app runs offline, needs no account and calls no server until you sign in. Snapshots and backups collect quietly beside the text. A folder is a dull thing to get excited about. It is also the one thing on this page that would survive both companies closing.
Sudowrite says little about storage on the pages we read. Projects follow you between sessions, which suggests its servers, and we found no statement about working offline. You can take your work out as a Word file, a .zip of a project, or a .csv of Story Bible sections, and its FAQ is clear that it claims no rights over what you put in.
Choosing Whose AI Reads Your Book
Sudowrite’s pages don’t mention bringing your own key or running a local model. Shiro has three routes, and you can mix them task by task.
A local model runs on your computer, through the llama.cpp that comes with Shiro, or through Ollama or LM Studio. The text goes as far as 127.0.0.1, which is not very far. Your own key works with OpenRouter, Anthropic, OpenAI, Google, Mistral or a custom endpoint. A Cloud plan includes hosted AI with no keys at all, and its chat requests go through OpenRouter.
Whichever you pick, the What Shiro sent panel lists every request, and a scene marked ai: never stays hidden from all of them. In Manual mode, edits wait as proposals until you say yes.
On training, the two apps say the same thing. Sudowrite’s FAQ says it doesn’t train on your writing, and Shiro never trains models on your writing. What a model provider does is a separate question, with its own terms. A local model is the one route where the question goes away.
Where Sudowrite Is Ahead
Producing fiction is the reason Sudowrite exists, and if you want a lot of it, quickly, start there. Muse was made for this. Shiro has no model of its own, so what you get depends on what you connect, and a small local model on an old laptop will write like a small local model on an old laptop. Shiro’s Continue and its rewrites, from Tighten to Sharpen dialogue, are real tools, but they share an app with a great many other things.
Sudowrite also asks for fewer decisions. Nobody has to compare models by how much memory they need. It describes a mobile app that shares projects with your laptop, and Shiro has no phone app yet. And Shiro is new.
We’ve read Sudowrite’s site. We haven’t run the same chapter through both, so we won’t tell you which writes better. Its trial needs no card, so try it on a scene you know well and judge for yourself.
Moving Over
Export from Sudowrite as Word, then import the .docx. Italics, comments and footnotes come across, and you split the file into scenes by headings, page breaks or a marker line. Shiro has no importer for Story Bible files. You can retype the entries, or let Find characters and places propose World entries from the text, if you have an AI switched on.
The Questions People Ask
Is Shiro a good Sudowrite alternative if I mostly use AI to draft?
It can draft: Continue writes from a sentence up to the next scenes, with up to three variants as ghost text. But drafting is one part of Shiro and the whole point of Sudowrite. If that’s all you want, try Sudowrite first.
How much is Sudowrite really?
The $10 you’ll see is the yearly rate for Hobby & Student. Paid month to month, that plan is $19. Professional is $22 and Max $44 a month on yearly billing, and we didn’t find their monthly rates.
Can I use my own API key or a local model?
In Shiro, yes. It takes keys for OpenRouter, Anthropic, OpenAI, Google, Mistral or a custom endpoint, and runs local models through its bundled llama.cpp, Ollama or LM Studio. Sudowrite’s pages mention neither.
Can I bring a Sudowrite project into Shiro?
Yes, through Word. Export a document or a merged project as .docx, then import it and split it by headings, page breaks or a marker line. There’s no importer for Story Bible files, so those entries need retyping or a pass with Find characters and places.
Sources: Sudowrite pricing, Sudowrite FAQ, Sudowrite on mobile, Sudowrite privacy policy, Exporting from Sudowrite