The use of natural indicator from red cabbage extract can also be used to monitor the titration using colorimetry since the anthocyanin pigment of red cabbage ranges in the absorption of visible light from pH 2 to pH 12. Previous studies used computer software, such as Photoshop, to analyze the red-green-blue composition of the titration solution at various intervals, making the indicator a suitable and easily accessible measure of the pH of the vinegar titration accurate to 0.3 pH. However, due to the expensive software subscription for Adobe Photoshop and the better accuracy and conveniency of the Ruolan pH meter, we selected the pH meter for this at-home experiment.