Ultrasound calibration is a methodological approach within medical physics, bioengineering, and imaging science focused on ensuring the accuracy and reliability of ultrasound systems and quantitative measurements. This involves assessing and adjusting parameters such as acoustic pressure, time-of-flight, frequency, and spatial resolution using standardized procedures, phantoms, and reference standards, which is essential for achieving reproducible results, enhancing diagnostic accuracy, and enabling comparable research and clinical data across different devices and studies.