Lingocubes is a language-learning kit authoring service provided by Charmpi LLC, a Massachusetts limited liability company, which operates Lingocubes, with its principal place of business in Massachusetts ("Charmpi", "Lingocubes", "we", "us"). You can reach us at hello@lingocubes.com.
This Privacy Policy explains what personal information we collect when you use lingocubes.com (the "Service"), what we do with it, and what choices you have. We've tried to keep it short and plain.
This policy applies to everyone who uses the Service. If you're in the EU/UK, the GDPR sections below describe your additional rights. If you're a resident of California, Virginia, Colorado, Connecticut, Utah, or other US states with consumer privacy laws, those laws give you additional rights that we describe in Section 7.
We collect only what we need to run the Service.
We send the minimum necessary data to the following services to run features. Each has their own privacy policy.
| Service | What we send | Why |
|---|---|---|
| Anthropic (Claude) | Your prompts, uploaded source material, and cube text | Kit generation, AI editing |
| OpenRouter, which forwards to Google (Gemini) | Your prompts + uploaded source material, including photos | Reading photos you upload; backup model when the primary one fails |
| OpenAI | Audio you upload or record; your prompts if our other AI providers are unavailable | Speech-to-text; backup kit generation |
| Microsoft Azure (Speech) | Cube text + voice settings; your audio while you record | Text-to-speech; live transcription while recording |
| ElevenLabs | Cube text + voice settings (premium voices, and some mixed-language text) | Premium text-to-speech |
| Stripe | Billing details, subscription state | Payment processing |
| Railway | Standard request metadata; our database and files are stored on Railway servers | Hosting our servers |
| Amazon Web Services (S3) | Audio files we synthesize for your cubes | Storing the audio cache |
| Amazon Web Services (SES) | Your email address | Sending sign-in links and account email |
| Google Fonts | Visitor IP and browser/device info when loading the Fraunces, Inter, and JetBrains Mono webfonts | Site typography |
We do not sell your personal information to third parties. We do not share your content with anyone outside the processors above, except as described in Section 5 below.
We use:
We do not use third-party analytics or advertising trackers.
By default, kits you create are private to your account. You can change that explicitly:
Lingocubes staff may access your kits and uploads when (a) you ask us for support, (b) we are investigating abuse, security issues, or billing disputes, or (c) we are legally required to.
| Data | Retention |
|---|---|
| Account + profile | While your account is active |
| Kits + uploaded source material | While your account is active |
| Cached audio files | Retained while the source kit exists; purged when the kit (or the account) is deleted |
| Server logs | 90 days |
| Stripe billing records | Per Stripe's policy + applicable tax law (typically 7 years) |
| Magic-link tokens | 15 minutes from issue, or until used (whichever comes first); expired and used rows are periodically purged |
When you delete your account (see Section 7), we delete or anonymize your data within 30 days, except where we are legally required to keep records (e.g., billing for tax purposes).
You can:
If you are in the EU/UK, you additionally have the right to object to processing, request restriction, and lodge a complaint with your local data protection authority. Our lawful bases under GDPR are: performance of contract (running the Service for you), legitimate interest (security, abuse prevention, product improvement), and consent (where applicable, e.g., optional analytics).
If you are a resident of California, Virginia, Colorado, Connecticut, Utah, or another US state with a comprehensive consumer privacy law, you have the rights described above (access, correction, deletion, portability) under your state's law. We do not sell personal information and we do not share it for cross-context behavioral advertising; we do not have a "Do Not Sell or Share My Personal Information" link because there is nothing to opt out of. We do not use personal information to make automated decisions that produce legal or similarly significant effects about you.
To exercise any of these rights, email hello@lingocubes.com. We will not discriminate against you for exercising them.
Our servers, AI providers, and storage providers may be located outside your country (the United States, the European Union, and elsewhere). By using the Service, you understand that your data may be processed in those locations. For EU/UK users, we rely on standard contractual clauses or equivalent safeguards with our processors.
Lingocubes is not directed at children under 13. We do not knowingly collect personal information from children under 13; if we learn that we have, we will delete it (US COPPA). If you are between 13 and 16 and located in the EU/UK, please make sure you have a parent's or guardian's consent before creating an account (GDPR Art. 8 — member states may set this between 13 and 16).
If you are a teacher using classroom features with minor students, you are responsible for obtaining the consents required by the laws applicable to your students (e.g., COPPA for US students under 13, FERPA if you are in a US school context, GDPR for EU students).
We use industry-standard measures: HTTPS for all traffic, magic-link auth (no stored passwords), encrypted storage, and access controls. We maintain a Written Information Security Program ("WISP") consistent with Massachusetts data security regulations (201 CMR 17.00) covering Massachusetts-resident personal information.
No system is perfectly secure; if we become aware of a breach affecting your data, we will notify you and any required authorities (including under Massachusetts G.L. c. 93H and other applicable state breach-notification laws) as quickly as we reasonably can.
We will update this policy from time to time. When we make material changes, we will update the "Last updated" date and notify active users by email and/or in-app notice. Continued use of the Service after the effective date means you accept the updated policy.
Questions, requests, or concerns: hello@lingocubes.com.