Civil Engineering · Concrete
Concrete Nominal Mix (IS 456:2000)
Cement, sand and aggregate quantities for IS 456:2000 nominal mixes (M5–M20 only — M25 and above require a design mix under IS 456, not covered here).
Standard method — stated scope limits apply
Mix & Volume
Choose a grade and volume.
About This Calculation
IS 456:2000 nominal mixes give fixed cement:sand:aggregate ratios (like 1:1.5:3 for M20) for ordinary-grade concrete, without needing a full mix design process — a practical, code-sanctioned shortcut for M5 through M20 grades specifically. Higher grades (M25 and above) are required by IS 456 itself to use a proper design mix instead, since a fixed ratio can no longer reliably guarantee the target strength at that level.
Frequently Asked Questions
Why does the calculator use a 1.54 "dry volume factor"?
Dry, loose materials (cement, sand, aggregate) take up more volume than the same materials once compacted into wet concrete, because of the air voids between particles before mixing — 1.54 is the standard, widely-used factor to convert a target wet (finished) concrete volume into the dry material volume you actually need to procure.
Why does the M20 result come out to about 8 bags of cement per cubic metre?
That figure follows directly from the 1:1.5:3 ratio and the 1.54 dry volume factor — it also happens to closely match the "8 bags per m³ for M20" figure very commonly cited in Indian construction practice, which is a useful cross-check that the calculation method is sound.
Can I use this method for M25 or higher grades?
No — IS 456:2000 itself requires M25 and above to use a design mix (based on target mean strength, water-cement ratio, and specific aggregate properties), not a fixed nominal ratio. This calculator deliberately does not offer those grades, rather than apply a method the code says isn’t valid for them.
Does this account for moisture in the sand or aggregate?
No — real site batching needs to adjust water content and aggregate weight for actual moisture/bulking, which varies day to day. Treat this calculator’s output as a material quantity estimate for procurement, not a final batching instruction.