How to use the pile cap calculator
This calculator helps you estimate rectangular pile-cap concrete and a stated steel allowance. It is intended for quantity takeoffs, early budgets and checks against a measured schedule. Start with the dimensions or quantities for one clearly defined item of work. Enter values in the units shown beside each field; millimetres and metres are not interchangeable.
Steel intensity is an editable estimating assumption, not a designed quantity. This rectangular model does not deduct pile heads or model triangular caps.
Worked example
Two 2 m × 2 m × 0.8 m caps contain 6.4 m³. At an assumed 150 kg/m³, the budget allowance is 960 kg.
Before you order
Compare the result with your drawings and supplier information. Keep the original net quantity separate from allowances, and round purchasing quantities only at the ordering stage. Check whether delivery, labour and related materials belong elsewhere in your estimate. If the drawing or specification changes, update the inputs and record the revised basis instead of reusing an earlier total.
For the concepts behind this calculation, read Rebar (Reinforcement Steel), Concrete Grade, Wastage Factor.
Common questions & estimating checks
What formula does the pile cap calculator use?
Volume = L × W × D × quantity; steel = volume × assumed kg/m³ — all calculations run directly in your browser using the exact inputs entered above.
How do you calculate a worked example?
Two 2 m × 2 m × 0.8 m caps contain 6.4 m³. At an assumed 150 kg/m³, the budget allowance is 960 kg.
What should be checked before ordering or pricing?
Verify dimensions against approved drawings, check supplier product yields and pack sizes, and keep net measured quantities separate from wastage or commercial risk allowances.