Abstract: The present subject matter relates to a vehicle mileage optimization system (300) for optimizing mileage of a vehicle by informing user about correct gear and speed combination. The vehicle mileage optimization system (300) has a speed and fuel measuring module (305) coupled with a processor (301) to collect speed and fuel data of the vehicle. Further, the vehicle mileage optimization system has a mileage and distance estimation module (306) coupled with the processor (301) to estimate fuel efficiency and correct gear and speed combination in the vehicle based on the collected speed and fuel data.