Rock drilling is performed in construction and mining works for creating voids in rock, excavating rock material and mostly blasting. The main purpose of drilling is to create a cavity in which explosive material can be placed by applying mechanical energy to the rock. The difficulty and ease of drilling depends on the rock's resistance to drilling. This resistance varies according to the physical and mechanical properties of the rocks. The drillability of rocks is expressed as the ratio of the hole size to the duration of the drilling process as a result of the studies carried out in the field or laboratory environment. Rock drillability can also be determined by drilling rate index (DRI) values determined based on the values ​​obtained from the fragility test (S₂₀) and Sievers miniature drilling tests (SJ) in the laboratory environment. However, the sample preparation processes of the samples to be used in the brittleness test and miniature drilling test methods are very laborious and time-consuming. In this case, it makes it difficult to determine the DRI values. For these reasons, as in estimating many physical and mechanical properties, it is estimated by indirect test methods, which are easier to determine/measure and give fast results, with rock properties. Within the scope of this study, the DRI values of the rocks were tried to be estimated by using the Shore, Schmidt and Leeb hardness values of 11 different carbonate origin rocks and indirect methods such as point load strength index and ultrasound wave velocity. Relationships between DRI values and values obtained from indirect experimental methods were examined by simple regression analysis. It was determined that there was a higher correlation (r = 0.96) between Leeb hardness value and DRI values compared to other indirect methods, albeit relatively. It has been shown that DRI values of rocks can be estimated quickly, practically and economically with Leeb hardness values before drilling works.