The Spectroscopy Calculator allows you to calculate absorbance, transmittance, concentration, molar absorptivity, or path length based on UV-Vis spectroscopy and the Beer-Lambert law. By entering the known values, the tool computes the unknown parameter, helping you analyze how light interacts with chemical solutions. This calculator is useful for chemistry students and researchers to study solution properties, interpret UV-Vis data, and understand the quantitative relationship between light absorption and concentration.