Privacy policy

Account information — when you sign up, our authentication provider Clerk handles your account: email address, name, and (if you use social sign-in) the basic profile your provider shares. We never see or store your password.

Learning and lesson records — the exercises you complete, homework answers, quiz results, skill-radar scores, your bookings and lesson history, messages with your teacher, the study sets made after your lessons, and notes your teacher leaves. This is the core of the product: your teacher plans lessons from it.

Your goal and study plan: your answers when you join (what you study and, for school subjects, your school year; goal and target date, why you study, what matters to you, time available, your level and past study, anything you tell your teacher) and the goal your teacher confirms. Your teachers and PAIdojo's founder can see them.

Live lessons — during a video lesson, your camera, microphone, any screen you share and the shared board travel between you and your teacher through LiveKit. Lessons are not recorded: the video and sound are not stored anywhere. What is kept is the study set made from the lesson and your teacher's notes.

Study sets — after a lesson, your teacher's study-set tool sends the lesson material to DeepSeek to draft your summary, flashcards and quiz: the teacher's notes and remarks, the lesson topic and date, the names and text of pages or photos the teacher adds, and your level and subject. Scanned pages and photos are first sent, as they are, to Google Cloud Vision to read their text. We never add your name to what we send, but what your teacher writes and the pages they add are sent as they are. Your teacher checks every set before you see it.

Speaking practice — speaking exercises use your browser's built-in speech recognition: your browser sends your voice to its own speech service (for example Google in Chrome, Apple in Safari) and hands our page the text. We score that text on your device and keep only the result. PAIdojo never receives or stores the recording.

AI practice — the messages you write to Tsumugi or Ask AI, and your answers when you ask for an AI explanation or AI grading in a quiz, are sent to DeepSeek together with the lesson words or question they are about, to generate the reply. Your conversations with Tsumugi and Ask AI are not stored; we keep only a count of the AI messages you have used. An AI explanation or grade you ask for in a quiz is saved with your quiz results, so you can read it again, and your teacher can see it. We never add your name or email address to what we send — but anything you type yourself is sent as you wrote it. If you use the AI helper when you set up your study plan, what you type into it is sent to DeepSeek, together with today's date and the choices you have already picked, to suggest answers for your plan. We never add your name. The conversation is not stored — we keep only a count of its messages — and nothing goes into your plan until you check it yourself. Your teacher (or PAIdojo's founder) can ask our AI assistant about your progress, to plan your lessons. For that, DeepSeek receives your study-plan choices (what and why you study, what matters to you, your goal and target date, a change of goal you asked for, the time you have, your level and past study), the goal your teacher confirmed, your progress numbers, the dates of your last and next lesson with that teacher, the next one's length and how many lessons since the goal, and your study sets (with the textbook and the place you stopped at, as noted by your teacher) with your quiz results, including the questions you missed (with the answer you picked, or a short answer you typed) and the ones you flagged. We never send the note you wrote for your teacher, the notes on your flags, or anything else you wrote about yourself. We take your name and contact details out of everything we send wherever our system recognises them, including a goal you wrote in your own words (your name, and any e-mail address, phone number or link). The conversation is not stored — we keep only a count of its messages. If you are a teacher, what you type into the assistant is sent to DeepSeek with the student's name and contact details taken out wherever our system recognises them.

Notifications — if you turn them on, our reminders reach your device through your browser's push service (for example Google for Chrome, Apple for Safari, Mozilla for Firefox). The message is encrypted on the way, so that service cannot read it.

Device storage & cookies — we use localStorage and cookies for things like your language choice, saved drafts, and sign-in session. Our visitor counts are anonymous: no cookie, no visitor ID and no IP address. We do not run third-party advertising or tracking tools.

To deliver lessons, practice and the study sets made from your lessons, to show your real progress to you and your teacher, to schedule and charge for lessons, to answer your messages and fix problems you report, and to keep the service safe. We do not sell your data, and we do not use it for third-party advertising.

Learning records are kept while your account is active — they are your record, and deleting them would erase your history with your teacher. When you ask us to delete your account, your personal data is removed from active systems.

Some things are never kept: lesson video and sound, speaking-practice audio, your conversations with Tsumugi, Ask AI and the study-plan helper (we keep only the count), and your teacher's conversations with the AI assistant about you (we keep only the count). Pages and photos read for a study set are processed and not stored by the reading service; the study set made from them stays with your account.

Backups that may still hold deleted data are overwritten within 35 days.

Clerk — account creation, sign-in, and session management.

DeepSeek — AI replies for Tsumugi, Ask AI, the study-plan helper, the teachers' AI assistant, AI explanations and AI grading, and the drafts of after-lesson study sets.

Google — Cloud Vision reads the text of scanned pages and photos teachers add to study sets, and emails to support@paidojo.com are read and answered in Gmail. If you use Chrome, Google also handles its speech recognition and notifications, and your sign-in if you choose to sign in with Google.

LiveKit — real-time video, sound, screen sharing and the shared board in live lessons. Nothing is recorded.

Stripe — payment for credits. You enter your card details on Stripe's own page; we never see or store your full card number.

Amazon Web Services (AWS, Tokyo region) — hosting for the site, our servers and stored data, and the mail system for support@paidojo.com.

jsDelivr and YouTube — some pages load open-source code and dictionary files from the jsDelivr network, and teachers' introduction videos play from YouTube in privacy-enhanced mode. Like any website you visit, they see your IP address.

Each provider processes data only to provide its service to us, under its own privacy terms. Some are outside Japan: Clerk, Stripe, LiveKit and Google are US companies, and DeepSeek processes data in China.

PAIdojo is for learners from primary school to adults. For a child under 16, a parent or guardian creates the account, books the lessons and makes any request about the child's data (see section 6). A child's records are seen only by the child's teacher and by PAIdojo's founder for support, and we never add a child's name to what we send to AI services.

When an account is first used, we ask who will study with it. If it is for a child under 16, the parent or guardian confirms this and agrees to the Terms and this Privacy Policy for the child. We keep that answer with the account, and the child's teacher can see that it is a child's account.

You can ask to see the personal data we hold about you, correct it, get a copy of it, or delete your account and its data. Email support@paidojo.com; we answer within a reasonable time, and a deletion removes your data from active systems. For a child under 16, the parent or guardian makes the request.

For privacy questions or requests (access, correction, deletion), email support@paidojo.com — a real person (the founder) reads every message. The contact page lists every other channel.