To create and validate a straightforward, accurate, and affordable UV-visible spectrophotometric method for calculating Calendulla officinalis and nelumbo nucifera in accordance with ICH Q2 (R1) guidelines. A UV-spectrophotometric technique has been devised for the simultaneous quantification of calendulla officinalis and nelumbo nucifera in a formulation of niosomal gel for the treatment of dermatitis. The stock solution is made using methanol as a solvent, and subsequent dilutions are made in distilled water. Calendula officinalis and nelumbo nucifera calibration standards were created, and absorbance was measured at the wavelength of maximum absorption. The linearity and range of the calibration curve of concentration vs. absorbance were computed. Additionally, it demonstrates that nelumbo nucifera and Calendulla officinalis both display absorption maxima at 320 nm and 254 nm, respectively. In the concentration ranges of 2–10 g/ml for Calendulla officinalis and 10–50 g/ml for nelumbo nucifera, respectively, the system followed Beer's law. According to ICH standards, the method was verified for linearity, range, accuracy, precision, and recovery studies. The routine examination of Calendulla officinalis and nelumbo nucifera in the formation of niosomal gel was therefore found to benefit from the suggested method's rapidity, specificity, precision, accuracy, and cost-effectiveness as a quality control tool. A simple, precise and cost-effective UV- visible spectrometry method for the estimation of niosomal gel was developed. The said method was developed using economical percentage of organic phase in aqueous media as solvent. Said validated UV- visible method can be efficiently used for the estimation of Calendulla officinalis and nelumbo nucifera in bulk as well as formulation. Keywords: UV- visible spectrometry, Calendulla officinalis, Nelumbo nucifera, validation