Privacy Policy

This page explains what data NihongoViet (nihongoviet.com) collects while you study, what we use it for, who we share it with and what rights you have.

  • Most lessons are open to everyone, no account needed. An account saves your progress and review schedule.
  • We store only what you need to sign in and pick up where you left off: your email, display name and study progress.
  • No ads, no analytics or tracking tools, and we never sell data to anyone.

1.Data we collect

  • Account details: your email, display name, JLPT level (if you choose one) and password. Passwords are stored only as a bcrypt hash — nobody, including us, can read the original.
  • Signing in with Google: your email, name and Google account ID (see section 3).
  • Study progress: the words, kanji and grammar patterns you have studied, your review schedule, completed and saved lessons, recently opened lessons, quiz and JLPT mock exam results, and listening progress.
  • Verification codes: the code emailed when you sign up (expires after 10 minutes) and password reset links (expire after 1 hour).
  • Technical data: IP address, browser type and time of access, recorded in server logs. IP addresses are also used to limit repeated failed sign-in attempts.

We do not collect phone numbers, home addresses, profile photos or payment details. NihongoViet is free and has no payments.

2.How we use your data

  • To create your account, sign you in, verify your email and reset your password.
  • To save your progress, schedule reviews, count your study streak and let you continue where you stopped.
  • To send emails your account needs: verification codes and password reset links. We do not send marketing email.
  • To keep the service running, find and fix errors, and prevent unauthorized access and abuse.

We do not use your data for advertising, and we do not sell or rent it to anyone.

3.Signing in with Google

When you choose “Sign in with Google”, we ask only for basic access: your email, name and Google account ID. We never receive your Google password and do not access Gmail, Drive, contacts or any other data in your Google account.

This data is used only to create your account and sign you in: your email is your username and your name becomes your initial display name (you can change it on your Profile page). We do not share data received from Google with third parties and do not use it for advertising.

Our use of information received from Google adheres to the Google API Services User Data Policy, including the Limited Use requirements. You can remove NihongoViet's access at any time at myaccount.google.com/permissions.

4.Cookies and browser storage

  • Sign-in cookies: refresh_token keeps you signed in for up to 30 days; it is HttpOnly, so scripts on the page cannot read it. auth_session only records that you are signed in so the right page opens.
  • Language cookie: NEXT_LOCALE remembers whether you chose the Vietnamese or English interface.
  • Browser storage (localStorage): a short-lived sign-in token, display settings (light/dark, sound, focus mode), an unfinished review session and which lessons you have listened to or read. This stays on your device and is removed when you clear the site's data.

We do not use advertising or tracking cookies. Embedded YouTube videos may set YouTube's own cookies (see section 5).

5.Sharing with third parties

We use only the providers needed to run the service, and each receives only the data its job requires:

  • Vultr: hosts the servers that run the app and its database.
  • Cloudflare: all traffic passes through Cloudflare's network for encryption and attack protection, so Cloudflare sees IP addresses and browser requests. Lesson audio files are also stored on Cloudflare.
  • Google: handles Sign in with Google, and Gmail delivers verification and password reset emails, so Google sees the email address and the content of those messages. For pronunciation, our server sends the Japanese word or sentence to be spoken to Google's text-to-speech service — with no information about you.
  • YouTube: some listening lessons are embedded YouTube videos. When you open them, your browser connects directly to YouTube, which may set cookies and collect data under Google's policies.

Data may be processed on servers outside Vietnam. Beyond the cases above, we disclose data only when required by law.

6.Storage and security

  • All connections use HTTPS. The database is not reachable from the internet.
  • Passwords and session tokens are stored only as hashes.
  • Changing or resetting your password signs out every other device immediately.
  • The database is backed up daily, and each backup is kept for 14 days.
  • Server logs have a fixed size and overwrite themselves, so they are kept only briefly.

Account details and study progress are kept for as long as your account exists. No system is perfectly secure; if an incident affects your data, we will tell you by email.

7.Your rights

  • View and edit your display name and JLPT level, and change your password, on your Profile page.
  • Request a copy of your data, a correction, deletion of your data or deletion of your account: email [email protected] from your account's email address.
  • Remove Sign in with Google access at myaccount.google.com/permissions.
  • Stop using the service at any time.

8.Children

NihongoViet is for anyone learning Japanese, but we do not knowingly collect data from children under 16 without the consent of a parent or guardian. If you are a parent and believe your child has created an account, contact [email protected].

9.Changes to this policy

When this policy changes, we update this page and the effective date at the top. If a change significantly affects how your data is used, we will announce it on the site or by email before it applies.

10.Contact

For privacy questions or data requests, email [email protected].

Related documentTerms of Service