Purpose <p>Xylopic acid (XA) is a bioactive isolate of the dried African pepper fruit, <i>Xylopia aethiopica</i> (Annonaceae) that has been variously reported to possess diverse biological activities. This work sought to determine the thermodynamic characteristics of XA under high and low temperature conditions and other structural features.</p> Methods <p>XA was isolated, its purity determined by high-performance liquid chromatography (HPLC), its structure characterized by spectroscopic means and further verified by powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SCXRD). Its heat capacity was then determined using a Quantum Design Physical Property Measurement System (PPMS) at a low temperature range of 1.9–305&#xa0;K, the data generated fitted to theoretical and empirical models and thermodynamic functions calculated.</p> Results <p>The standard molar heat capacity, enthalpy, and entropy values at 298.15&#xa0;K were found to be 2314.446&#xa0;J.mol^− 1.K^− 1, 1261.08&#xa0;J.mol^− 1, 2366.62&#xa0;J.mol^− 1. K^− 1 respectively. Thermogravimetric analysis (TGA) of XA over the temperature range (25&#xa0;°C –330&#xa0;°C) showed a 69.37% total weight loss. The enthalpy of fusion value of 334410.1&#xa0;J.mol^− 1 with corresponding heat capacity of 334606.1&#xa0;J.mol^− 1.K^− 1 were found by differential scanning calorimetry. XA was determined to be 74.68% crystalline, with the average values for crystallite size, dislocation density and microstrain as 17.8260&#xa0;nm, 3.9470 × 10^− 3 nm^− 2 and 11.7455 × 10^− 3 respectively from the PXRD data obtained.</p> Conclusion <p>This work reports for the first time, novel thermodynamic functions of XA under low and high temperature conditions and its structural characteristics such as the degree of crystallinity, crystallite size, dislocation density and microstrain. Our findings would serve as a useful guide for further research on XA including drug development and formulation such as crystalline and amorphous solid dispersions.</p>