Thermochronology offers critical constraints on rock cooling and exhumation histories, enabling quantitative assessments of landscape evolution and its interactions with tectonic and climatic forcings. These interpretations increasingly rely on numerical models capable of linking measured thermochronometric data to realistic thermal and kinematic scenarios. Among such tools, the Pecube code provides a unique 3D thermal‑kinematic framework that explicitly couples tectonic and geomorphic processes with predicted thermochronometric observables, which has been widely used for reconstructing the tectonic and topographic evolution of mountain belts as well as crustal thermal structure. In this contribution, we introduce PecubeGUI, a new open‑access graphical user interface (GUI) that modernises and greatly enhances the accessibility of Pecube. Alongside the interface, we present substantial updates to Pecube, including the implementation of contemporary radiation‑damage models for apatite and zircon (U–Th)/He thermochronometers, multi-kinetic models for fission-track annealing, and the integration of ultra-low temperature thermochronometers such as the apatite <sup>4</sup>He/<sup>3</sup>He and trapped‑charge methods, the latter being in active development. These additions expand the ability of Pecube to resolve low‑temperature cooling signals, particularly at Quaternary timescales, where increased temporal resolution is essential for understanding landscape evolution.</p> <p>By lowering the technical barrier to Pecube modelling and broadening the toolkit available to users, PecubeGUI aims to foster wider adoption and stimulate new applications across the thermochronology, geomorphology, and tectonics communities.