EC · 01Time planning utility

Mark the start.
Measure the duration.
Solve the missing time.

ROSENBERG is a Poland-based software company building practical mobile applications for time planning and everyday digital workflows. Our first product, Event Calculator, helps users calculate durations, find start times, project end times, convert minutes, and save time calculations in one clean mobile workspace.

Poland-based companyMobile app developmentPublic website — no account requiredTime planning utility
Time Solver3 modes
Known values
Two values in. One answer out.
01START+END=DURATION
Calculate Duration
02END+DURATION=START
Find Start Time
03START+DURATION=END
Find End Time
Local-first · no accountGoogle Play ↗
00:0006:0009:0012:0015:0018:0024:00
Software brief · 02

Time utility software for practical planning.

ROSENBERG creates mobile products with clear interfaces, careful testing, and everyday value. Event Calculator is built for people who need simple duration calculations, start/end time solving, minute conversions, saved calculations, and recent history without accounts or unnecessary complexity.

Application · 03

Event Calculator

Calculate event durations, find start or end times, save time calculations.

Calculate Duration

Input start and end dates/times to find total duration displayed in hours, fractional hours, and minutes.

START + END = DURATION

Find Start Time

Determine when an event needs to start based on its planned end time and required duration.

END + DURATION = START

Find End Time

Calculate when an event will finish by entering its start date/time and duration in days, hours, and minutes.

START + DURATION = END

Privacy Policy · 04

Privacy Policy

Effective date: August 5, 2026. This Privacy Policy applies to the Event Calculator mobile application and related public information services operated by ROSENBERG.

What information does the Application obtain and how is it used?

Event Calculator does not collect, log, store, sell, or share personal information when you download and use the app. Registration is not required.

If the Application is used with an active internet connection, technical protocol data such as an ephemeral IP address may be transmitted to facilitate network connectivity, but this data is not retained or used for tracking.

No accounts or authorization

The ROSENBERG website and Event Calculator app do not require account creation, login, registration, user profiles, member areas, protected pages, or authorization flows.

Precise location information

This Application does not collect precise real-time location information from your mobile device.

Third-party access

Since the Application does not collect personal information, no personal data is shared with third parties. ROSENBERG does not sell personal data.

Data Retention

Event Calculator does not collect or retain personal data through normal app use. Because no personal information is collected, there is no personal data retention period for app usage data.

If you voluntarily contact ROSENBERG by email or through another communication channel, the provided contact information may be kept only as long as necessary to respond to your request, maintain reasonable communication records, and comply with applicable legal obligations.

Data Deletion

Because Event Calculator does not collect personal information through normal use, there is no app-held personal data to delete. Uninstalling the Application removes the app from your device.

If you voluntarily provided information to ROSENBERG by email or another direct contact method, you may request deletion by contacting support@rosenberg.ink.

Local calculation records

If start dates, start times, end dates, end times, duration values, days/hours/minutes entries, calculated duration results, calculated start times, calculated end times, fractional hours, exact minute conversions, saved calculations, recent history, date picker preferences, time picker preferences, app settings, or local calculation records are saved by the app, they remain local to the user’s device unless a future feature clearly states otherwise.

Responsible use notice

Event Calculator is a personal event-time calculation and planning utility. It is not a calendar booking service, event ticketing platform, meeting scheduling SaaS, employee time tracking system, payroll time clock, travel timer app, countdown alarm app, project management tool, legal timekeeping system, professional billing timer, or replacement for official calendars, legal records, workplace scheduling systems, payroll tools, contracts, transport schedules, medical timing requirements, or personal judgment.

Children

The Application is not intended for children under 13 years of age, or a higher age where required by applicable law. ROSENBERG does not knowingly solicit data from children or market to them.

Security and breach notification

Because the Application does not collect personal data, the risk of personal data exposure is minimal. However, no security system is completely secure. If a breach occurs involving information voluntarily provided to ROSENBERG, ROSENBERG will notify affected users as required by applicable law.

Changes to this Privacy Policy

ROSENBERG may update this Privacy Policy from time to time. Material changes will be reflected by posting the updated Privacy Policy with a new effective date.

Your consent

If you voluntarily provide information to ROSENBERG and processing is based on consent, you may withdraw that consent at any time without affecting processing carried out before withdrawal.

Contact · 05

Contact ROSENBERG

For privacy requests, product questions, support, or development inquiries, contact ROSENBERG using the details below.

Address51 s.51 Al. Stanów Zjednoczonych Warszawa, 04-026 Poland
Phone+48 884 054 473
Emailsupport@rosenberg.ink
info@rosenberg.ink
development@rosenberg.ink