Binaralt: Planning of observations for variable systems BinarAlt is a Python-based script designed to simplify and accelerate the planning of observation nights, with a particular focus on periodic variable systems with known ephemerides. What sets BinarAlt apart from other tools or popular web platforms is its specialized functionality for periodic systems. For each observation night, it calculates the altitude of each target above the horizon as a function of time, together with the orbital phases being observed during the night. Additionally, BinarAlt generates a file listing the next 200 predicted primary eclipses for the targets. To further streamline the preparation process, BinarAlt creates a detailed logfile containing essential information about the observation nights, such as moon illumination percentages, twilight times, and target rise times.