The performance of interlocking concrete tiles depends strongly on the proportions of cement, water, fine aggregate, and coarse aggregate used in their production. This study investigated two concrete mix proportions developed for interlocking tiles with a target characteristic compressive strength of 30 MPa. River sand in Zone 2 and 10 mm granite chippings were used as fine and coarse aggregates, respectively. The reported specific gravities of the fine and coarse aggregates were 2.66 and 2.71. Two mixes were designed using SCALE 149 software. Mix 1 had a reported proportion of 320:190:760:1195 and a water-to-cement ratio of 0.594, while Mix 2 had a proportion of 275:160:790:1240 and a water-to-cement ratio of 0.58, for cement, water, fine aggregate, and coarse aggregate, respectively. Five bone-shaped specimens were produced for each mix, demoulded after 24 h, cured for 28 days, and tested for compressive strength using a 200 kN compression testing machine. The reported compressive strengths for Mix 1 were 34.0, 37.7, 40.2, 39.6, and 30.7 MPa, giving a mean strength of 36.44 MPa. Recalculation from the five individual results gives a sample standard deviation of 4.02 MPa. Mix 2 produced strengths of 43.7, 34.1, 36.8, 40.2, and 37.4 MPa, with a mean of 38.44 MPa and a sample standard deviation of 3.65 MPa. Using the characteristic-strength approach reported in the source study, fck = f? ? Ks with K = 1.64, the calculated characteristic strengths are 29.85 MPa for Mix 1 and 32.45 MPa for Mix 2. Thus, Mix 2 was the preferred mix among the two investigated proportions because it exceeded the 30 MPa target while using less cement than Mix 1. The findings provide a practical basis for selecting a mix proportion for interlocking concrete tiles, although the limited number of specimens warrants further validation with larger experimental datasets and additional durability tests.