Privacy Policy.
The short version: content you send for pseudonymization is never stored permanently. The token map lives in memory for one session and is irreversibly wiped when the TTL expires or you end the session.
Account data, the content you process, and short-lived technical logs — each handled differently.
4 h on Free, up to 24 h on paid plans. Then the token map is gone, for good.
Only tokens ever reach a model. Original values never leave your side.
01Data controller
The controller of personal data processed in connection with the use of Synonym is Synonym s.r.o., Bratislava, Slovakia. Questions about data processing go to hello@usesynonym.eu.
02What data we process
We distinguish three categories, because they are handled completely differently:
2.1 Account data
Name, e-mail address and a password hash (never the password itself), plus the plan you chose. If you generate an API key, we store only its SHA-256 hash and the last four characters — the full key is shown exactly once, when it is generated.
2.2 Content you process through the service
Files (CSV/XLSX), text and PDFs you upload for detection and masking are processed in memory and are not stored permanently. The mapping from tokens to original values (the vault) lives only for the length of a session — in an in-memory store with an enforced TTL — and is deleted both automatically when the TTL expires and on request (an API call that ends the session). The original file or text itself is not stored on the server after processing.
2.3 Technical and operational data
IP address and basic request metadata that we need for rate limiting, error diagnostics and abuse protection. These logs are kept for a short period and are not used for any profiling.
03Legal basis
We process data on the basis of (Art. 6 GDPR):
- performance of a contract — your account, billing details on paid plans, and the pseudonymization service itself;
- legitimate interest — security logs, rate limiting, protection against API abuse;
- consent — where we explicitly ask for it (for example marketing communication, should we ever introduce it).
04Retention periods
| Type of data | Kept for |
|---|---|
| Account (name, e-mail, password hash) | Until you close the account or ask for deletion |
| Session mapping (vault) | The session TTL — up to 4 h on Free and 24 h on Starter, Pro, Business and Enterprise; sooner if you end the session manually |
| Password-reset token | 60 minutes from the request, or until used |
| Security / operational logs | Short-term, only for diagnostics and abuse protection |
05Who we share data with
We share the content you process with nobody except the destination you choose yourself — for example the LLM provider you configure for the “Ask the model” feature. Only tokenized data goes there, never original values. Beyond that we work with ordinary technical sub-processors (hosting, infrastructure) who process data on our behalf under a data-processing agreement. We do not sell your data and do not share it for third-party marketing.
06International transfers
Our infrastructure runs primarily within the EU. If you choose an LLM provider based outside the EU (for example in the US), we send it — on your instruction — only tokenized content, not original personal data. Where data is transferred outside the EU/EEA through our sub-processors, we rely on standard contractual clauses or another valid mechanism under the GDPR.
07Security measures
- passwords are hashed (we never store a readable password);
- API keys are stored only as a SHA-256 hash;
- token mappings live only in memory with a TTL, never as a permanent database table;
- all communication with the service runs over an encrypted connection (HTTPS).
08Cookies
We use only functional cookies that are strictly necessary for signing in and keeping a session (session cookie, CSRF token). We do not use third-party cookies for tracking or advertising, and no third-party analytics or advertising script runs on the site.
09Your rights
As a data subject you have the right under the GDPR to:
- access your personal data;
- rectification of inaccurate data;
- erasure (“right to be forgotten”), where this does not conflict with another legal obligation;
- restriction of processing, or to object to it;
- data portability in a machine-readable format;
- lodge a complaint with the Office for Personal Data Protection of the Slovak Republic (dataprotection.gov.sk) if you believe processing breaches the GDPR.
You can exercise any of these rights with a plain e-mail to hello@usesynonym.eu.
10Changes to this policy
We may update this policy from time to time, mainly as features are added. The current version is always on this page with the effective date at the top; we notify you of material changes by e-mail or directly in the app.