This study aims to assess the performance of compression ignition (CI) engine powered with various biodiesels. The engine used for this test was a single-cylinder, water-cooled, naturally aspirated, CI engine. The biodiesels used in this study were neem methyl ester (NME), mahua methyl ester (MME), cottonseed methyl ester (CME), tamanu methyl ester (TME) and Albizia saman methyl ester (AME). According to the results, the TME-operated CI engine had 2.69%, 10.53%, 6.31% and 5.49% higher brake thermal efficiency than the MME, NME, CME and AME, respectively, without exhaust gas recirculation (EGR). Tamanu biodiesel outperformed the other test fuels in terms of performance and emissions. As a result, tamanu biodiesel was chosen as the best fuel for further testing. The results showed that tamanu biodiesel emitted more oxides of nitrogen (NOx) emissions than diesel. EGR could be used with the CI engine, resulting in a significant reduction in NOx emission. Compared to tamanu biodiesel without EGR conditions, the percentages of EGR 5%, 10% and 15% used with TME-operated CI engine produced 9.9%, 18% and 21.3% less NOx emission. The combination of EGR and tamanu biodiesel resulted in a slight increase in hydrocarbon, smoke and carbon monoxide emissions but a substantial reduction in NOx emissions. According to the study's findings, tamanu biodiesel with 10% EGR demonstrated optimal engine characteristics while having a low environmental impact.