Privacy policy
Last updated: 9 November 2026
This policy explains which personal data cypher handles when you use cypher chat (our web app), the cypher API and this website, why we handle it, who else receives it, how long we keep it, and which rights you have.
1. Who is responsible
cypher (in formation)
Email: hello@gocypher.ai
Full company details follow after incorporation.
We are a company based in Switzerland. The law that applies to how we handle your data is the EU’s General Data Protection Regulation (GDPR) and, for the company, the Swiss Federal Act on Data Protection (DSG).
2. In short
- Answers come from Claude models, run by Anthropic in the United States (section 5).
- Our servers, database and backups are at Hetzner in Falkenstein, Germany.
- Your chats stay until you delete them. We don’t sell your data and show no advertising.
- This website sets no cookies and loads nothing from other servers. The app keeps in your browser only what it needs to work (section 15).
3. What we handle
| Data | What it is | Where it comes from |
|---|---|---|
| Account | Your account ID; your name, email address, phone number and username as our sign-in service holds them | You, when we set up your account (cypher is invite-only for now) and when you sign in |
| Sign-in | Your password, stored only as a hash by our own sign-in service, and any passkeys you add, of which it keeps the public key | You |
| Chats | Your messages (text and images), the answers, chat titles, your projects, which model wrote each answer and summaries of long chats | You, and the AI models that answer |
| API | Each API key’s name, a short hint of it and a hash (we can’t read a key back), when it was last used; conversations you create through the API, with their messages | You, when you make a key or call the API |
| Credit | Your balance, the credit we add to your account, and what each answer cost, with the tokens, model, exchange rate and markup it was priced with | Created as you use cypher |
| Technical logs | Our gateway (Traefik) does not write access logs. Our sign-in service logs, for each sign-in request it handles, the visitor's IP address, the request method and path, and the browser's user agent, and notes sign-ins from a new IP address or location with the account's email address. These logs are kept in our own log store (Loki) for 31 days. The sign-in service also keeps in its database, for each account, the IP addresses and browsers it has signed in from, the IP address of each active session, and security events with their IP address. That database is in our Postgres, so it is in our backups too (section 10). Our own services log IDs and counts, but an error message, ours or the database’s, can include part of a message’s text | Your browser or app |
4. Why we use it, and the legal basis
The articles below are the GDPR’s; for the company, the Swiss DSG applies as well (section 1).
| Purpose | Legal basis (GDPR) |
|---|---|
| Providing cypher: your account, your chats, answers from AI models, the API and your credit | Contract, Art. 6(1)(b) |
| Keeping cypher secure and preventing abuse | Legitimate interests, Art. 6(1)(f): a safe service that keeps to our providers’ rules |
| Keeping accounting records | Legal obligation, Art. 6(1)(c) |
| Answering you when you write to us | Contract, Art. 6(1)(b), or legitimate interests, Art. 6(1)(f) |
5. AI model provider
To answer you, cypher sends your new message, the earlier messages of the chat (or a summary of them, section 8) and the chat’s instructions to the model that answers. Each answer shows which model wrote it.
| Provider | What for | Where |
|---|---|---|
| Anthropic Ireland, Limited, 6th Floor, South Bank House, Barrow Street, Dublin 4, D04 TR29, Ireland | Claude models | United States |
Anthropic processes the data on our behalf, under a data processing agreement.
Transfers outside the EU and Switzerland: Anthropic processes the data in the United States.
How long Anthropic keeps request data, and whether it uses it to train models: Anthropic deletes it within 30 days, unless it must keep it longer to enforce its usage policy (a request its safety systems flag: up to 2 years) or by law, and doesn't use it to train its models.
6. Personal details in your messages
The provider in section 5 receives the personal details that are in your messages, so cypher is not anonymous. Leave other people’s sensitive details out of a chat unless you need them.
7. No tracing for now
We don’t record traces of your chats for now: no tracing or analytics tool receives your messages or the answers. If we start, we’ll tell you before it takes effect (section 15).
8. Long chats
When a chat gets long, an AI model writes a summary of its earlier messages, and later answers get the summary instead of every word. The summary is written from the chat’s text, by the provider in section 5, and stored with the chat.
9. Other recipients
| Recipient | What for | Where |
|---|---|---|
| Hetzner Online GmbH, Industriestr. 25, 91710 Gunzenhausen, Germany | Our servers, databases and backups | Falkenstein, Germany: the servers, and the object storage for backups and logs |
| Authorities and courts | Only where the law obliges us |
For now, our sign-in service sends no emails: during the pilot, you get your first password directly from us.
cypher takes no payments for now, so no payment provider receives your data.
We don’t sell personal data and show no advertising.
10. How long we keep it
| Data | How long |
|---|---|
| Chats, projects, messages, summaries | Until you delete them. A deleted chat disappears at once and is erased from our database after 30 days |
| API conversations | Until you delete them; then they are erased at once |
| Text of API calls without a conversation | Not kept: only what the call cost is recorded, with your credit |
| Your account | Until it is closed: write to us to close it (section 13). Then its content, and everything in cypher’s database that links the remaining records to you, is erased after 30 days. Your account with our sign-in service (your name, email address and password) isn’t part of this: it stays until you ask us to erase it (section 13) |
| Credit records | As long as tax law requires, also after your account is closed, without the link to your chats. |
| Technical logs | 31 days in our log store (Loki). On the servers themselves, each running service also keeps its most recent log lines (about 50 MB at most) until newer lines push them out or the service is replaced; these have no fixed end date |
| Backups | 35 days. Deleted data stays in backups until they expire |
| API keys | Until you revoke them; they stop working when your account is closed. A revoked key’s hash stays, so the same key can never be issued again; its name is erased with your account’s content, 30 days after the account is closed |
11. Security
- TLS protects your data on the way: between your device and cypher, and between cypher and the AI provider.
- In cypher’s own database, your account details are encrypted (AES-256-GCM). Our sign-in service keeps your name and email address in its own database in readable form.
- We store passwords and API keys only as hashes, so we can’t read them back.
- Each user’s chats are kept apart in the database by row-level security.
- Chats are not end-to-end encrypted: cypher has to read a message to send it to a model.
12. Automated decisions
Auto chooses the model that answers: for now Claude Sonnet, with Claude Haiku as its backup; later by the kind of question.
13. Your rights
You can:
- ask for a copy of your data (Art. 15)
- have it corrected (Art. 16)
- have it erased (Art. 17)
- have its use restricted (Art. 18)
- take it with you in a common format (Art. 20)
- object to uses based on legitimate interests (Art. 21)
- withdraw a consent at any time; what happened before stays lawful (Art. 7(3))
Write to hello@gocypher.ai. You can also complain to a data protection authority: in the EU, for example the one where you live or work (Art. 77); in Switzerland, the Federal Data Protection and Information Commissioner (FDPIC).
14. Age
cypher is for people aged 18 and over.
15. Cookies and storage in your browser
cypher keeps in your browser only what it needs to work: no analytics, no advertising, nothing that follows you to other sites.
| What | Where | What for | How long |
|---|---|---|---|
| The sign-in session cookie | Set by our own sign-in service | Keeps you signed in, so a new tab or the installed app signs you in without asking again | At most 30 days from when you sign in; it stops working after 7 days unused, or when you sign out. Signing out ends it at our sign-in service. When that can’t be reached at the time, the app signs you out on that device only and tells you so; when the tab is closed before signing out has finished, the cookie can stay too, without a message. The cookie then works on until it runs out or a later sign-out ends it, so signing in there again may not ask for your password |
| Your sign-in tokens and the sign-in’s settings | The app’s session storage, for that tab or window only | Show cypher that it’s you | Until you sign out or close the tab or the app’s window |
| A few marks: whether the sidebar is collapsed, whether you installed the app, and your sign-outs on this device (a count and a flag, nothing personal) | The app’s local storage | Keep the app as you left it, and sign out every tab when you sign out in one | Until you clear your browser’s data |
cypher.theme, only if you choose a theme with the button in the header |
This website’s local storage | Your choice of light or dark | Until you clear your browser’s data |
| The app’s files | The browser’s cache, through the app’s service worker | The app opens fast and starts offline. It keeps only the app itself, never your chats, answers or account details | This version’s, until a new version replaces it. An earlier version’s, while a window still runs it, at most three. Files the app loads only when needed, such as code highlighting for a language: at most 60, the oldest going first. All of it goes when you clear your browser’s data |
| What you were typing (or had just sent, if its answer hadn’t started) when the app reloads: for an update, or to sign you in again after your session ended. With it, the chat’s address and your account’s ID at our sign-in service | The app’s session storage, for that tab only | Your unsent text comes back in the same chat after the reload, and only to the account it was typed in | Removed as soon as it’s back, or when you sign out or close the tab |
All of this is needed for the service you asked for, so we don’t ask for consent and show no cookie banner.
16. Changes
We tell you about important changes by email or in the app before they take effect.