Visual techniques for qualitative assessment of roads, which rank the roads either good or not, have been widely used by the International Confederation of Transport. Although there are quantitative techniques, such as IRI (International Index Roughness), the use of these techniques involves a higher cost technique compared to the visual one due to the fact that there is a need of special and quite expensive equipment. In this work we developed a new quantitative indicator of roads able to evaluate and compare them in terms of its surface quality without relying on visual analysis. A low-cost acquisition system based on an analog 3-axis accelerometer and a microcontroller was developed. Also, it was developed an algorithm able to evaluate and rank the road on a scale ranging from 0 to 5. Two roads visually rated as good and bad were used as references. It was tested 3 different types of roads, with or without holes. Both tests were conducted with a vehicle running at 40, 50 and 60 km/h. The results showed that the greater the amount of holes or unevenness the worst the quality indicator and that this depends on the speed of the vehicle. It was concluded that a quantitative analysis of road might be automatically done by using a low cost measuring system.