M20
M20 mix design
See how a common grade moves from specified strength into target strength, w/c selection and trial proportions.
Read M20 guide →INDIA · IS 10262 MIX PROPORTIONING
Build the preliminary mix—and see why each number is there.
Use project strength, durability limits, material properties, sand zone, aggregate size, workability, admixtures and moisture conditions to create a transparent starting mixture. The calculation is designed to be checked, trialled and adjusted with real materials.
IS 10262:2019 contextThe current calculator path is built around the 2019 proportioning workflow, with a legacy 2009 option where needed.
Durability stays visibleProject and IS 456 limits are kept separate from strength-based choices so the controlling value can be checked.
Moisture mattersFine and coarse aggregate moisture and absorption feed into batch quantities and corrected water.
Trial mix, not certificateThe result is a starting proportion for verification with actual materials—not an approved project mix.
GRADE GUIDES
Use M20–M50 as a starting point, not a fixed recipe
A grade identifies characteristic strength. It does not uniquely determine cement, sand, aggregate or water quantities. The same grade can require different mixtures when exposure, material properties or workability change.
M30
M30 mix design
Follow a higher-strength example while keeping durability and workability decisions visible.
Read M30 guide →M40
M40 worked benchmark
Use the detailed example to understand the calculation trail and compare it with your own inputs.
Read M40 guide →THE DECISIONS THAT CONTROL THE MIX
Strength, durability and materials have to agree
| Design step | What the calculator shows | What you should verify |
|---|---|---|
| Target mean strength | Characteristic strength plus the adopted variability margin | Correct standard deviation basis and project quality history |
| Water-cement ratio | Requested value, durability cap and adopted controlling value | Current project/IS limits and actual strength evidence |
| Water demand | Starting water adjusted for workability, aggregate conditions and admixture input | Actual slump response, aggregate shape and admixture trial data |
| Cementitious content | Calculated content and entered minimum/maximum checks | Applicable durability/specification limits and binder system |
| Aggregate split | Fine/coarse allocation and absolute-volume balance | Current IS 383 grading and approved source combination |
| Batch correction | SSD basis converted using moisture/absorption inputs | Current stockpile moisture at production time |
FIELD CONTROLS
Protect the design after it leaves the spreadsheet
Water added through wet sand, poor consolidation or inadequate curing can defeat a carefully calculated starting mixture.
Aggregate moistureCorrect both batch mass and free water when site aggregates are not at SSD condition.
VibrationConsolidate systematically while avoiding missed pockets, dragging and unnecessary over-vibration.
CuringProtect the moisture and temperature conditions needed after placement.TOOLS
Move between calculation, verification and planning
FULL CALCULATION
IS mix design calculator
Build a preliminary mix with a visible calculation trail and moisture correction.
Open calculator →WATER CONTROL
Water-cement ratio guide
Separate strength-driven selection from durability limits and field water additions.
Read guide →AGGREGATES
Aggregate calculator
Explore fine/coarse allocation using project inputs rather than a copied fixed percentage.
Open tool →TRIALS
Trial-mix planner
Compare nearby w/c values and record how a trial responds before settling on production quantities.
Plan trials →COST
Material cost
Apply your own local rates to the calculated concrete quantities.
Estimate cost →CARBON
Carbon estimate
Explore how constituent quantities influence an indicative embodied-carbon total.
Estimate carbon →BEFORE SITE USE
Do not approve concrete from a calculator alone.
The useful output here is a transparent starting point. Final project use depends on current standards and specifications, actual material test data, laboratory or plant trials, field controls and the responsible approval process.
- Confirm the current applicable BIS documents and project specification.
- Use current aggregate grading, specific gravity, absorption and moisture data.
- Verify admixture performance with the selected cementitious system.
- Record fresh properties, yield and strength during trials.
Optional detailed report
The India calculator can generate a formatted calculation report and Trial Mix Sheet from your own inputs. It is a documentation aid, not a mix approval, material test certificate or substitute for a qualified project review.