Effective date: October 21, 2026
This Privacy Policy explains how FullCastBook ("FullCastBook", "we", "us") handles personal data when you use fullcastbook.com and the audiobook generator on it (the "Service"). If anything here is unclear, write to support@fullcastbook.com.
The short version
- We use your manuscripts, voice samples and generated audio only to provide the Service to you.
- To analyse your text and voice it, we send the relevant parts to third-party AI providers. They are listed below.
- We do not sell your personal data, and we do not use your manuscripts or audio to train our own AI models.
- You can ask us at any time for a copy of your data or to delete your account and everything in it.
Information we collect
Account information. When you sign up with email we store your email address, your name if you give it, and a securely hashed password. If you sign in with Google or GitHub (where offered), we receive your name, email address and profile picture from that provider. We never see your Google or GitHub password.
Content you upload. Manuscripts and ebooks (for example EPUB, PDF, DOCX or TXT files), text you paste, the chapters and characters detected in them, your cast and voice choices, delivery directions and sound tags you write, and any other project settings.
Voice samples. If you use voice cloning, we store the recording you upload and the voice created from it. You may only upload your own voice, or a voice whose owner has given you explicit permission (see our Terms of Service).
Generated content. The audio files, chapter markers and exports we produce for you.
Payment information. Payments are handled by our payment providers. We receive the plan or credit pack you bought, the amount, currency, transaction ID and payment status. We never receive or store your full card number.
Usage and device information. IP address, browser and device type, sign-in sessions, pages visited, the features you use, credit balance and usage, generation history and error logs.
Sign-up attribution. When you create an account we record the website that referred you, campaign parameters in the link you used (UTM tags) and your approximate country, so we can understand which channels bring people to the Service.
Support conversations. Messages, emails and attachments you send us.
How we use your information
- To provide the Service: read your files, find chapters and speaking characters, cast voices, generate and export audio, and keep your projects available to you.
- To run your account: sign-in, security checks, email verification and password resets.
- To process payments, grant and track credits, and manage subscriptions.
- To answer your questions and support requests.
- To keep the Service safe: prevent fraud, abuse of free credits, spam and attacks, and enforce our Terms.
- To understand and improve the Service, mostly through aggregated statistics.
- To send service emails such as receipts, security notices and important changes. We send marketing emails only where the law allows, and every one has an unsubscribe link.
- To comply with legal obligations.
If you are in the European Economic Area or the United Kingdom, our legal bases are: performing our contract with you (providing the Service and processing payments), our legitimate interests (security, fraud prevention, product improvement and sign-up attribution), your consent (analytics cookies, which you can withdraw at any time), and legal obligations (for example, keeping tax records).
AI processing and the providers we use
FullCastBook is built on third-party AI models. When you run a generation, we send only what that step needs:
- Language models receive the text of your manuscript, chapter by chapter, to find the structure, identify who is speaking and prepare it for narration.
- Voice and text-to-speech providers receive the lines to be spoken, the voice selected for each character and your written directions, and return audio. Voice samples you upload for cloning are sent to the voice provider to create your voice.
Today these requests go through the KIE API platform (kie.ai) to models from providers such as Google (Gemini) and ElevenLabs. Each provider processes the content under its own terms and privacy policy, which may include keeping it for a short time to detect abuse. If we change or add AI providers, we will update this list.
We also rely on these service providers:
- Cloudflare — hosting, content delivery, our database, file storage (Cloudflare R2, where your uploads and generated audio are kept) and email delivery.
- Payment providers — Stripe and Creem for card payments and subscriptions, and Alipay or WeChat Pay where those options are offered.
- Sign-in providers — Google and GitHub, only if you choose to sign in with them.
- Email providers — to send account and service emails, for example Cloudflare Email Service or Resend.
- Analytics — such as Google Analytics or Plausible, if enabled, and subject to your cookie choice.
These providers may only use your data to provide their services to us. We may also disclose information if the law requires it, to protect the rights and safety of our users or others, or as part of a merger, acquisition or sale of assets, in which case this policy will continue to apply to your data.
Cookies and analytics
We use a small number of cookies that the Service needs to work: your sign-in session, your language and theme preference, and your cookie choice. These do not track you across other websites.
Analytics cookies, such as Google Analytics, load only after you accept them in the cookie banner where it is shown. Cookie-free analytics may be used without a banner. You can change your choice by clearing this site's cookies in your browser, which brings the banner back. We do not currently use advertising cookies; if that changes we will update this policy and ask for your consent where the law requires it.
Storage and retention
Your uploads and generated audio are stored in Cloudflare R2, and account data in our database hosted on Cloudflare. We keep them while your account is active so your projects stay available to you.
- When you delete a file or project, or ask us to delete it, we remove it from active storage within 30 days. Backups that may contain it are overwritten within a further 30 days.
- When you ask us to delete your account, we delete your profile, uploads, voice samples and generated audio within 30 days.
- We keep payment and tax records for as long as the law requires, even after you delete your account.
- Security and server logs are kept for a limited time, normally no more than 90 days, unless we need them longer to investigate abuse.
Security
We use encrypted connections (HTTPS), access controls, and encryption at rest for sensitive settings and credentials. No online service is perfectly secure; if we learn of a breach that affects your personal data, we will notify you and the authorities as the law requires.
Your rights and choices
Depending on where you live, you may have the right to access your personal data, correct it, delete it, receive a copy in a portable format, object to or restrict certain processing, and withdraw consent at any time.
To use any of these rights, email support@fullcastbook.com from the address on your account. We may need to verify your identity and will reply within 30 days. If you are in the EEA or UK, you also have the right to complain to your local data protection authority.
If you are a California resident: we do not sell your personal information and we do not share it for cross-context behavioral advertising. You will not be treated differently for exercising your privacy rights.
International transfers
We and our providers process data in the United States and other countries that may have different data protection laws from yours. Where the law requires it, we rely on safeguards such as the European Commission's Standard Contractual Clauses for these transfers.
Children
The Service is not directed to children under 16, and we do not knowingly collect their personal data. If you believe a child has given us personal data, contact us and we will delete it.
Other people's information in your content
Manuscripts can contain information about real people. You are responsible for having the right to upload and process any personal data contained in your content.
Changes to this policy
We may update this policy as the Service changes. We will post the new version on this page with a new date, and for material changes we will also tell you by email or in the Service before they take effect.
Contact
FullCastBook — support@fullcastbook.com