UltraVox XT is a software tool that analyzes sound, including ultrasonic vocalizations. The signal is displayed in real-time in a waveform and spectrogram. Frequency range, amplitude, duration, and time gaps are used to determine calls that fit within automated or manually-defined criteria. Calls are then labeled with user-defined names. UltraVox XT provides a report with data, statistics, and spectrograms. It also plays back the recording in an audible (pitch-reduced) range. Data, audio files, and images are easily exportable. The data is fully compatible with EthoVision XT and The Observer XT for further integration of the vocalizations with other behavioral and physiological data.