Results
Enter values and click Calculate to see results. Use the unit toggle to match your project.
Tips
- Increasing water raises slump but may reduce strength and durability.
- Prefer admixtures when specifications limit w/c ratio.
- Account for real-time aggregate moisture to avoid over-watering.
FAQs
The estimate uses a user-set coefficient. Common starting points are ~5 L/m³ per 10 mm (metric) or ~1 gal/yd³ per inch (US), but aggregates, temperature, cement, and admixtures can change response significantly. Calibrate with site data whenever possible.
Usually yes. Higher water–cement ratio generally reduces compressive strength and durability. If the updated w/c exceeds specification limits, consider admixtures or consult the mix designer rather than adding water.
Start with the defaults and refine using field trials: record slump changes after small water additions and update the coefficient to match your mix, materials, and conditions.
Reducing slump by removing water in the field is not practical. Options include allowing the mix to rest, adding a stabilizer per supplier guidance, or rejecting the load if outside tolerances.
Moist aggregates contribute free water. Use the moisture contribution field to subtract that water from additions. Aggregate grading and shape also change slump response, so calibration is important.
Limits vary by exposure class and specification (often around 0.40–0.55). Always use the project’s approved limit. Enter it here to get a warning if the updated ratio exceeds the requirement.
No. This tool provides quick estimates and checks. Use it alongside approved mix designs, site procedures, and professional judgment.