<p>Precise evaluation of vehicular emissions in real-world conditions is essential for assessing air quality and determining the efficacy of emission control policies. A critical research gap exists regarding the comparative study between Bharat Stage VI (BS-VI) and BS-VI compliant vehicles in various diverse Indian driving conditions. Laboratory-based measurement often fails to captures detailed emission profiles in complex traffic conditions. This study addresses this gap by analyzing the emissions from BS-IV petrol, BS-IV diesel, and BS-VI petrol vehicles in Indian driving conditions using a portable emission measurement system (PEMS). We developed a novel framework that integrates vehicle specific power (VSP) with unsupervised techniques to identify and analyze the distinct emission profiles over various driving conditions. The best clustering algorithm’s results (<i>k</i> means) were used to compare and assess the emissions characteristics of BS-VI and BS-IV vehicles under various driving conditions. Result showed that CO₂ and NO_x emissions were highest for all three vehicle types during transitions from idle to minor acceleration and lowest during idling/creeping. BS-VI petrol vehicles demonstrated a substantial decrease (25 to 90%) in NO_x emissions compared to BS-IV petrol vehicles across different driving conditions. However, the difference in CO₂ emissions between BS-IV and BS-VI petrol vehicles was minimal (5%). The developed models can be a decision-support tool for policymakers to encourage responsible driving behavior and reduce vehicular emissions. This research is notable for its accurate, data-driven representation of real-world emissions. It offers policymakers a crucial tool for assessing emission regulations and driving patterns, encouraging eco-friendly driving practices.</p>