Globally, the environmental awareness is driving the research towards energy resources that are more beneficial to milieu. Biofuel is considered to be a remarkable option for that. Among the sources of biofuels, vegetable oils are the cheapest, easily available and in abundant quantity. However, some processes are needed to make vegetable oils suitable for engines because vegetable oils have certain detrimental properties. In this study, three potential feedstocks, namely, moringa, sesame and rice bran oils are critically investigated as potential sources for biodiesel production. The work was divided into several steps: firstly, the production of biodiesel from the three feedstocks; secondly, the measurement of the important physical and chemical properties of biodiesels; and finally, the development of mathematical equations with the help of polynomial curve fitting method for biodiesel–diesel and biodiesel–biodiesel blends to predict the most important properties, such as kinematic viscosity, flash point, calorific value, CFPP of the blended biodiesel. The experiment has shown that the three feedstocks can be considered to be feasible sources for biodiesel. It is seen from the experiment that biodiesel blends have notable effect on properties; for instance, the viscosity of the rice bran oil is improved to 5.1631 mm² s⁻¹ from 5.3657 mm² s⁻¹, when mixed with sesame biodiesel at a volume ratio of 3 : 1. Moreover, it is improved to 5.0921 mm² s⁻¹, when mixed with moringa biodiesel at a volume ratio of 3 : 1. Moreover, flash point and CFPP of rice bran biodiesel are also improved, when mixed with sesame or moringa biodiesel in any percentage.