Volume, bags, and cost estimator

Foundation Cost Calculator

Answer first: Estimate foundation concrete volume, bags, and cost from dimensions. Compare bags with ready-mix, check waste, and review the total before ordering.

10 ft x 10 ft x 4 in

about 1.23 yd3 and ~56 bags

At 0.6 ft3 per 80 lb bag with 10% waste.

1 cubic yard

about 45 bags at 0.6 ft3

Compare with local ready-mix minimums.

Interactive calculator

Foundation Cost Calculator

Enter dimensions. Compare bags with ready-mix delivery.

Volume

1.36 yd3

Bags

62

Ready-mix

$367

Bagged

$310

Interactive workflow

Run the numbers, then save or export the project

View planning notes
Best reviewed quote
Ready-mix supplier A
Red flags
0
Proposal total
$3,824
Pour window
171 min
Local cost defaults and ZIP memory

Saved cost defaults

Reuse bag price, ready-mix price, delivery fee, and waste factor across quote reviews.

Local assumptions
ZIP47474
1 yd3 as bags$259
1 yd3 ready-mix$475
Break-even3.3 yd3
  • 80 lb bag price: $6
  • Ready-mix price per yd3: $165
  • Delivery + short-load: $310
  • Wait-time rate: $95 per hour

Save this estimate or download a PDF report

The PDF report uses the current calculated result. Save the estimate first when you want to reuse the inputs later.

Dimensions or known volume
Enter slab length, width, and thickness, or switch to known volume.
Bag count at your yield
See bag count at your selected yield alongside ready-mix yards and cost.
Delivery and fee awareness
Check minimum billable yards, delivery fees, and effective cost per yard.

What ordinary foundation cost calculators miss

The useful result is the delivery minimums, waste, fees, and cost comparison.

Review the concrete quote
Benchmark saysReplace with local inputNext check
One number, no costCompare bag count, bag cost, and ready-mix cost side by side.Order the cheaper path after confirming local minimums.
Ignores wasteAdd a waste factor for real pour conditions.Use 5% for clean forms, 10% for typical pours.
No delivery checkSee minimum billable yards before assuming ready-mix is available.Call the supplier to confirm minimums and access.

Foundation Cost Calculator checklist

Use these checks before relying on the estimate.

Signal to checkWhat it meansNext step
Bag yieldThe bag yield matches your mix and bag size.Check the bag label for cubic feet per bag.
Waste factorThe waste percentage matches site conditions.Increase waste for uneven ground or complex shapes.
Ready-mix minimumThe supplier minimum load is confirmed.Ask about minimums, lead time, and access.
Delivery and accessThe truck can reach the pour location.Confirm chute reach and any pump needs.

Related concrete planning tools

Move from a single calculation into a purchase, proposal, or pour-day decision with connected calculators and checklists.

How do I use this calculator?

Enter your slab length, width, and thickness. The calculator converts to cubic yards, adds waste, and shows bag count and cost.

How many bags are in a cubic yard?

At 0.6 ft3 per 80 lb bag, one cubic yard (27 ft3) takes about 45 bags. Adjust the bag yield for other sizes.

Should I use bags or ready-mix?

For small pours under 1-2 yards, bags can be cheaper. For larger pours, ready-mix is usually cheaper per yard. Compare both with your local prices.

Does this include delivery fees?

Yes. Enter delivery fee, access fee, and minimum billable yards to see full ready-mix cost alongside bagged cost.

Planning disclaimer

This calculator provides planning estimates. Confirm actual prices, minimums, and site conditions with your supplier before ordering.