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Biodiesel is oxygenated diesel fuel and a potential alternative made from animal fats and vegetable oils by conversion of triglycerides into esters via conventional transesterification either with or without the use of catalyst. Extensive utilization of biodiesel comes with several advantages over petroleum based diesel owing to renewable nature, superior flash point, potentially high biodegradability, lower toxicity, inherent lubricity and negligible sulfur contents. Nevertheless, several technical reasons including higher cost, poor low temperature flow properties, variable chemical composition and complete engine clogging make its excessive usage quite questionable and less popular in comparison with petroleum based diesel. Therefore, the present review was designed to overcome these shortcomings thereby taking a step forward towards sustainable developments by compiling various chemical and biochemical approaches such as fatty acids chain length reduction including direct blending and microemulsion, utilization of various antioxidants, ultrasound methods, microwave technologies and fatty acids chain extension constituting culturing, extraction, engineered β-oxidation, ω-oxidation along with double bond induction, fractionation with crystallization, thermolytic breakdown, catalytic cracking, oxidative cleavage, hydrolytic reactions and double bond removal through direct polymerization and formation of biobased epoxy resins. Various oxidative approaches include oxidation of double bonds, autoxidation of fats and addition of transition metal catalyst during simple oxidation. Some assisted transesterification techniques include ultrasound …