Analysis of slope stability is crucial for the design of many engineering processes such as open pit mine and highway. Slope stability is generally evaluated by limit equilibrium and numerical analyses, and rock mass classification systems. The slope height is used as the input parameter in many of these methods. Advanced methods such as LiDAR and TLS are expensive and time consuming and they require professional use. Therefore, researchers generally need to use simple methods for the measurement of slope height because of their cheapness, rapidity and portability. In this study, height of the rock slopes was determined with tape line, laser meter, altimeter, clinometer and geological compass. Measurements were taken from steep (90) and inclined slopes (75). Further, various models were developed in the laboratory for understanding the mechanism of methods in inclined slopes (45–90). The findings of methods used compared with each other and the reliability of the methods was discussed. Strengths and weakness of the methods were highlighted. This study indicated that some factors (measurement distance, slope width, the inclination of the ground, rugged surface in toe of the slope, etc.) can negatively affect the estimations of slope height.