Privacy Policy

Last updated: 23 October 2026

UAB Semka (“Semka”, “we”, “us”) provides free online imposition tools for print shops: the Gang Up Imposition calculator and the Roll Imposition calculator. This policy explains what personal data we process when you use semka.lt and why. We keep it to the minimum needed to run the tools and keep them secure.

1. Who is responsible for your data

The data controller is UAB Semka, Lithuania. You can reach us through the contact page.

2. Using the imposition tools

The Gang Up and Roll Imposition calculators work without registration or login.

• What you enter: sheet or roll sizes, layout sizes, quantities, bleed, non-printable edges, number of strips and, optionally, a price per m². These values are sent to our server only to calculate the layout and the result is returned to your browser. They are not linked to you, they are not saved to a database, and we do not use them for profiling or advertising.
• Do not enter personal data: the tools do not need names, e-mail addresses or customer details, so please do not type them into the input fields.
• Abuse protection: to prevent overloading the calculators we limit the number of requests per IP address (currently 120 per minute). For this we keep a short-lived counter identified by a one-way hash (SHA-256) of your IP address. The counter is stored in temporary server storage and is overwritten after the one-minute window.
• Error logs: if a calculation fails, we log a technical error message (not your input values) so that we can fix the problem.

3. Technical data

When you visit the website, our web server and hosting provider automatically process standard technical data: IP address, date and time of the request, requested page, browser and device type (user agent) and the referring page. We use it to deliver the website, keep it secure, detect abuse and fix errors. We do not use it for marketing.

4. Optional user account

You do not need an account to use the imposition tools. If you do create an account, we process:

• Account details: name, company name, e-mail address, telephone number and your password (stored only as a secure hash).
• Sign-in records: IP address, user agent, time and result of sign-in attempts, kept for security and abuse prevention.
• Service e-mails: messages needed to confirm your registration or change your e-mail address. We do not send marketing e-mails.

We keep account details while your account exists. You can delete your account in your account settings or by contacting us, after which your account data is erased, except where we must keep something to meet a legal obligation or to handle a security incident.

5. Why we process data (legal bases)

• Providing the tools you request and, where relevant, your account – performance of a contract or steps at your request (GDPR Art. 6(1)(b)).
• Security, abuse prevention and keeping the website running – our legitimate interests (Art. 6(1)(f)).
• Legal obligations, where applicable (Art. 6(1)(c)).

6. Who receives your data

• Hosting and e-mail providers that process data on our behalf to run the website and deliver service e-mails.
• Google Fonts: the website loads the Inter typeface from Google (fonts.googleapis.com). Your browser therefore sends your IP address and browser details to Google when a page loads. Google may process this data outside the EU/EEA.
• Authorities, if we are legally required to disclose data.

We do not sell your data and we do not use advertising or analytics trackers.

7. Data security

We protect data with technical and organisational measures such as access restriction, session validation, CSRF protection, rate limiting and hashed passwords. No system is completely secure, so please avoid entering sensitive information anywhere on the site.

8. Cookies

Cookies are small text files stored on your device. We only use cookies that are strictly necessary for the website to work: to keep your session, protect forms against forged requests and remember your cookie choice.

Semka does not use analytics or marketing cookies.

9. Your rights

Under the GDPR you have the right to access your data, have it corrected or erased, restrict or object to its processing, and receive it in a portable format. To use these rights, contact us through the contact page. You also have the right to lodge a complaint with the State Data Protection Inspectorate of Lithuania (Valstybinė duomenų apsaugos inspekcija, vdai.lrv.lt) or with the supervisory authority in your country.

10. Children

The website is intended for professionals and is not directed at children.

11. Changes to this policy

If we change how we process data, for example by adding saved projects or file exports to the tools, we will update this page and the date at the top.

12. Contact

Questions about this policy or your personal data: UAB Semka contacts.