Spectuner identifies spectral lines of interstellar molecules automatically. The code uses XCLASS (ascl:1810.016) for the spectral line model and SciPy for the peak finder. Spectral fitting is performed using article swarm optimization and the peak matching loss function. From frequency in a unit of MHz and temperature in a unit of K, Spectuner returns the combined spectrum, identification of the combined spectrum, and the identification of all candidates.