M25 Concrete Mix Design Calculator
Start with the standard M25 characteristic strength and see how the IS 10262:2019 proportioning method turns your project inputs into a preliminary mix. The calculator keeps the standard grade as the starting point but lets you replace material and project inputs with your actual values.
Standard starting values
The M25 value above is the standard grade designation. IS 10262:2019 says the Table 2 standard deviation may be assumed for the first instance; once adequate test results are available, the calculated standard deviation should be used.
What the calculator will determine
Questions this page answers
What is the target mean strength for M25? Using the Table 2 first-instance SD, it is 31.60 N/mm². Your target should be recalculated when actual project SD is available.
Does M25 automatically determine the final mix? No. Grade fixes the characteristic strength; the final proportions still depend on water-cement ratio, slump, aggregate grading, specific gravity, admixture performance, moisture and project durability requirements.