Privacy Notice

Version of 2026-11-12 · The German version is binding.

This notice explains which data Sprachfuchs processes about you, why, for how long and which rights you have.

1. Who is responsible?

The responsible party is Nils Niemann, c/o MDC#dev, Welserstraße 3, 87463 Dietmannsried, Deutschland (referred to below as “we”). Send privacy questions and requests under section 11 to support@sprachfuchs.com or by post to this address. After signing in, you can also contact us through “Feedback” in the profile menu. We do not have a data protection officer; at this size one is not required by law.

2. The essentials

Sprachfuchs helps you prepare for German examinations. We therefore store your account and what you practise.
Your writing and speaking contributions are sent for evaluation to AI providers that may process data in the United States and other countries (section 8). Without this, writing and speaking cannot be evaluated. Your name and email address are not sent with them.
Your voice recordings are deleted after evaluation, unless you have expressly consented to permanent storage (section 6.6).
We use no third-party advertising or analytics tools and load no fonts, scripts or images from other servers. The exception is the checkout page for Plus (section 6.11): only there does your browser load Paddle’s checkout script. Your browser is not given an identifier for recognition. We count visits from links to our website ourselves on our server, without cookies or disclosure (section 4.1).
We ask only for your year of birth, not your date of birth. Sprachfuchs is for people aged 18 or over.
You can download all your data and delete your account yourself at any time (“Me” menu).

3. Legal bases in brief

Where we rely on “legitimate interests”, the interest is safe, reliable and abuse-free operation. You may object for reasons arising from your particular situation (section 11).

Account, practice, evaluation and AI evaluation: contract for use (Art. 6(1)(b) GDPR).
Server logs, abuse protection, cost control, error reports, backups, feedback and moderation: legitimate interest (Art. 6(1)(f) GDPR).
Permanent recordings, community and reminder emails: your consent (Art. 6(1)(a) GDPR), which you may withdraw at any time.
Cookies and browser storage for sign-in and settings: section 25(2)(2) TDDDG (technically necessary).

4. Access data and hosting

The website is hosted by Hetzner Online GmbH (Germany), which provides servers and the domain on our behalf. The server is in Falkenstein, Germany. When you access the site, the server processes your IP address, time, requested address, response code and browser information. This is technically necessary to deliver the site and defend against attacks. Logs are kept only as long as necessary for these purposes.

Your IP address is also briefly used in memory to slow repeated sign-in attempts; it disappears when the server restarts.

4.1 Reach and campaign measurement (without cookies). To learn which of our advertisements, posts and partner pages bring visitors, our server counts visits to website pages and the registration page. We count only visits by day, page and campaign. The campaign is included in the link you clicked (for example utm_source, utm_medium, utm_campaign, plus click identifiers from advertising platforms, of which we remember only the type, not the value) and, if you come from another website, that website’s address without path and search terms. The information remains in the address as you move between our pages; nothing is stored or read on your device for this purpose. To estimate visitor numbers, we briefly calculate an in-memory value from a random daily key, your IP address and browser identifier. The value is not stored, the key changes daily and the value can no longer be assigned to a person afterwards. IP addresses and identifiers are not included in any count. Bots, prefetches and movement within our website are excluded. If you register, we store this origin information (source, medium, campaign, click-identifier type and entry page) on your account. This lets us see which advertising led to accounts and how far those accounts progress (confirmed, first examination, Plus). We do not share this information with advertising platforms. You may object (section 11); we then delete the origin information from your account.

5. Account and sign-in

Registration. Registration is open; an invitation code is optional and may grant a plan. While registration is closed, a code is required. We ask for email address, username, password, native language, target level, country and year of birth. We need this to create your account, send emails, display the interface in your language, preselect the appropriate level and verify your minimum age of 18. Without the required information we cannot create an account. During registration we record which version of this notice and the terms you accepted and when.

Password. We store only a hash (scrypt), never the password itself. When you set a password, we check whether it appears in known data breaches. For this purpose, a fraction (the first five characters) of a checksum is sent to “Have I Been Pwned”. The service learns neither your password nor your identity; the request comes from our server.

Confirmation. Your account can be used only after you confirm your email address. The link in the email signs you in immediately (the link is valid for 48 hours and can be used once). Accounts that are never confirmed are deleted after one year.

Session. After sign-in we set a session cookie. It contains only a random identifier (only its hash is stored in the database) and expires after 30 days. No consent is required for this (section 25(2)(2) TDDDG).

Browser storage. Your browser remembers settings on your device (display, language, text size and last view) and temporary state during an examination. This is necessary for the requested service and is not sent to us for analysis.

Email delivery. Confirmation and password emails are sent through Proton AG (Switzerland), which works for us as a processor. It sees the recipient, subject and content of the email.

6. What happens while you practise

6.1 Exercises and results. Your answers, scores, writing, speaking transcripts, evaluations and history are stored under your account until you delete it. Other accounts cannot see them. Administrators may view them for troubleshooting.

6.2 Mistake profile and training. From writing, speaking and pronunciation we store detected mistakes (the incorrect passage up to 200 characters, correction and category). We use them to create your personal mistake profile and training exercises. Only you can see it. This is an automated evaluation of your performance, used solely for learning and with no legal effect.

6.3 AI evaluation and AI conversation partner. An AI model evaluates writing and speaking transcripts. During speaking, an AI conversation partner talks to you and a language model generates its voice. You therefore write and speak with artificial intelligence, not a human. The evaluation is a practice estimate, not an official examination, and has no legal effect. There is no decision based solely on automated processing within the meaning of Art. 22 GDPR.

Only the relevant text, conversation transcript and recording are sent to providers, never your name, email address or username. Please do not write or say anything in exercises that you do not want to disclose, such as health data, addresses or information about other people.

6.4 Voice recordings. When you speak, your browser sends the recording to our server. It is sent from there to an AI provider for transcription and to our own evaluator for pronunciation comparison. The recording is then discarded. The text, evaluation, detected sound sequences and pause lengths remain (measurements, not audio data).

6.5 Pronunciation comparison. Comparison of your pronunciation with the target text takes place on our own server, not with a third party. The recording is there only while it is processed.

6.6 Permanent recordings (consent only). For tests and to improve evaluation, an administrator may permanently store recordings of your account if you have expressly consented. This is voluntary; your account works without consent. You may withdraw consent at any time (message through “Feedback” or to the address in the imprint); we then delete the stored recordings.

6.7 Protection against account sharing. An account is intended for one person. To detect whether an account is being passed to many people, at each sign-in we store two fingerprints, one from the browser type (“User-Agent”) and one from the network (the first parts of the IP address), generated with a secret key, together with a broad label such as “Chrome · Windows”. We store neither your IP address nor an identifier in plain text, and nothing is stored in your browser for this purpose. Entries are deleted after 90 days; only administrators see them and nothing is automatically blocked.

6.8 Activity. We store the time of your last activity (an overwritten value, at most once per minute) so administrators can see whether someone is online. No history or location data is created.

6.9 Quotas and costs. For each AI call we record the provider, model, amount (tokens, seconds and characters), cost and the account that triggered it. This limits the number of AI-evaluated modules (overall in the free plan and, in Plus, through a technical daily limit against misuse). If you delete your account, the record remains without a link to you as a cost record.

6.10 Feedback. If you write to us through “Feedback”, we store your message, the page from which you came and a shortened browser description.

6.11 Plan, free examination, cancellation and withdrawal.

Plan and start: We store which plan your account has (free or Plus), where it came from (gift, invitation code or purchase), its end date, your choices in the start assistant (examination profile and examination) and how many AI-evaluated modules you have started.
Paid contract: We also store the start, your express request for immediate start together with the version of the terms, receipt of a cancellation or withdrawal and whether a refund is pending.
Cancellation and withdrawal: With “Cancel contracts here” or “Withdraw contract”, we record receipt with the time and email confirmation to your account address. Cancellation is also possible without signing in: we then process the email address you enter and send a confirmation link. A link is valid for 24 hours and can be used once. Withdrawal is possible only after signing in.
Legal basis: the contract (Art. 6(1)(b) GDPR) and, for evidence of cancellation and withdrawal, our legal obligation and legitimate interest in keeping evidence (Art. 6(1)(c) and (f) GDPR).
Payment (Paddle): Plus is sold by our online retailer Paddle.com Market Limited (United Kingdom) as Merchant of Record. When purchasing, you enter your email address, country, postcode or region and payment details with Paddle. Paddle uses this data for payment, invoices, VAT, fraud prevention, refunds and buyer support and is itself the controller (not a processor acting for us). Its privacy notice is at paddle.com/legal/privacy. We receive only what we need for access: order number, plan, term, status (paid, cancelled or refunded) and subscription identifiers. We do not receive payment details such as card numbers. The legal basis is the contract (Art. 6(1)(b) GDPR). Checkout: During purchase, /kasse opens. Only there does your browser load Paddle’s script (cdn.paddle.com) and display Paddle’s checkout in an embedded window; Paddle then receives your IP address and browser information and may use technically necessary cookies or browser storage for payment and fraud prevention (section 25(2)(2) TDDDG). We load nothing from Paddle on other pages. While Plus is not available for purchase, nothing is sent to Paddle.

6.12 Reminder emails (consent only). If you consent during registration or later under “Me”, you occasionally receive emails about learning progress and Plus: two days after your free examination, a reminder about mistake training (only if you have not used it) and one week later a reminder about Plus (only if you do not have Plus and have not registered interest). Each type is sent at most once. We store your consent, when it was given and which types have been sent. Each email has an unsubscribe link; you can also withdraw consent under “Me” at any time. Emails are sent through Proton AG (section 8). Without consent, you receive only emails necessary for your account (confirmation, new password, cancellation and withdrawal).

7. Community (optional, adults only)

The community is available only if you expressly join. Without joining, there is no profile or score. If you join:

Others see only your nickname, profile picture and score, and only if you are discoverable or they are your friends. Others never see your name, username or email address.
Messages (text and voice) are available only between confirmed friends. They are stored on the server encrypted but not end-to-end encrypted: someone operating the server with its key could technically read them. We do not read them unless someone reports a message; administrators can then see it. Messages are deleted after one year; when you leave, messages you sent are deleted immediately.
Reports are stored with a copy of the reported message so that we can review them; completed reports are deleted after 180 days.
Profile picture. We resize it to 256 × 256, store it as WebP and remove metadata (location and camera). Upload only pictures showing you alone or people who have consented.
The legal basis is your consent by joining; you can withdraw it at any time by leaving.

8. Recipients and transfers to third countries

These service providers process data for us under data-processing agreements (Art. 28 GDPR):

Hetzner Online GmbH (Germany): server and domain.
Anthropic (our contractual partner is Anthropic Ireland, Limited; processing also takes place in the United States) and OpenAI (our contractual partner is OpenAI Ireland Ltd.; processing also takes place in the United States): AI evaluation and AI conversation partner (texts and transcripts), and for OpenAI additionally speech-to-text and speech output. We configure the exact providers and models in our settings and may change them.
OpenAI subprocessors: OpenAI uses further providers for data centres, support and review of reported content in several countries, including cloud providers in the EU, United Kingdom, United States and other countries. Content flagged as policy-violating may be sampled for review by providers that also operate in the Philippines. The current list is at openai.com/policies/sub-processor-list.
Anthropic subprocessors: Anthropic uses cloud providers (Google, Amazon and Microsoft), Cloudflare and providers for billing, support and fraud prevention operating in the United States and other countries (support also in South Africa and Canada). Your name and email address are not sent to Anthropic. The current list is at trust.anthropic.com/subprocessors.
Proton AG (Switzerland): confirmation, password, cancellation and withdrawal emails and mailboxes for requests to the addresses in the imprint. The EU Commission has recognised an adequate level of protection for Switzerland.
Imprint service (Germany): receives post at our imprint address and forwards it to us (for example letters, written withdrawals or official correspondence).
Our own error tracker (GlitchTip, operated by us): technical error reports without exercise content, names, email addresses or cookies. Browser reports go there directly and necessarily contain your IP address.
Have I Been Pwned (United States): only the first five characters of a password checksum, without a link to you (section 5).

For transfers to the United States and other third countries, providers and we rely on standard contractual clauses (Art. 46(2)(c) GDPR) or, where the recipient is certified, the EU Commission’s adequacy decision for the EU-US Data Privacy Framework. OpenAI Ireland Ltd. transfers input data to group companies and third parties outside the EEA only on one of these bases. We use provider interfaces whose terms do not allow submitted input to be used for model training. OpenAI retains inputs and answers for up to 30 days for abuse detection, but not for speech-to-text, unless a longer retention period is required by law. The imprint address can provide details about the safeguards.

Paddle.com Market Limited (United Kingdom) receives the data you enter when purchasing Plus and is an independent controller for it (section 6.11), not a processor. Paddle’s privacy notice applies to onward transfers. We do not otherwise disclose data unless legally required.

9. Retention

Account and learning history: until you delete your account.
Unconfirmed accounts: one year, then deletion.
Website visit counters (not personal): 24 months. Registration origin on the account: until account deletion.
Sign-in entries (fingerprints): 90 days.
Community messages: one year; reports 180 days after completion.
Voice recordings: only during processing; permanently stored recordings (with consent) until withdrawal or account deletion.
Consent to reminder emails and records of sent types: until withdrawal or account deletion.
AI cost record: without a link to you after account deletion.
OpenAI: inputs and answers up to 30 days for abuse detection (not for speech-to-text), unless a longer period is required by law.
Contract data (cancellation, withdrawal and payment evidence): for the retention periods required by commercial and tax law.
Backups: daily, the last 7 versions; deleted data may therefore remain in backups for up to 7 days.

10. Security

We protect data with encrypted connections (HTTPS), hashed passwords, strict account separation (including in the database), access restrictions and regular backups.

11. Your rights

You have rights of access (Art. 15), rectification (Art. 16), erasure (Art. 17), restriction (Art. 18), data portability (Art. 20), objection to processing based on legitimate interests (Art. 21) and withdrawal of consent with effect for the future (Art. 7(3) GDPR).

Access and portability: In the “Me” menu, “Download my data” downloads a machine-readable JSON file containing all data in your account. It does not contain your password or sign-in-measurement fingerprints.
Erasure: In the “Me” menu, you can delete your account and all its data yourself (with your password).
Everything else (rectification, restriction, objection and withdrawal): write to us using the address in section 1. We reply within one month and may ask you to verify your identity for security.

Complaint. You may complain to a data-protection supervisory authority, especially in the country where you live or work. The authority responsible for us is the Hessian Commissioner for Data Protection and Freedom of Information, PO Box 3163, 65021 Wiesbaden, Germany.

12. Required information, age and changes

Required registration information is needed for the contract; all other information is voluntary. There is no automated decision with legal effect for you. Sprachfuchs is for people aged 18 or over.

We update this notice when functions or the law change. We inform you in the app about material changes. The current version carries its date above.