Calculator
Formula used
Depth in feet = entered depth converted to feet.
Cubic feet = square feet × depth in feet.
Cubic yards = cubic feet ÷ 27.
Adjusted cubic yards = cubic yards × (1 + waste % ÷ 100) × (1 + compaction % ÷ 100).
Estimated cost = adjusted cubic yards × price per cubic yard.
How to use this calculator
- Enter the area in square feet, or enter length and width.
- Add the planned layer depth and choose its unit.
- Select the material, or choose Custom and enter density.
- Add waste, compaction, price, bag size, and truck capacity.
- Press Calculate to see cubic yards above the form.
- Use CSV or PDF buttons to save the result.
Example data table
| Area | Depth | Base cubic yards | Use case |
|---|---|---|---|
| 100 sq ft | 3 in | 0.93 yd³ | Small mulch bed |
| 500 sq ft | 4 in | 6.17 yd³ | Concrete slab |
| 1,200 sq ft | 2 in | 7.41 yd³ | Top dressing |
| 2,000 sq ft | 6 in | 37.04 yd³ | Gravel base |
Square Feet to Cubic Yards Guide
Square feet measure surface area. Cubic yards measure volume. A project needs volume when a flat area receives a real depth. Concrete pads, garden beds, gravel paths, playground mulch, and backfill all use this idea. The area tells how wide the layer spreads. The depth tells how thick that layer should be.
Why Depth Changes the Answer
One square foot at one foot deep equals one cubic foot. A cubic yard contains twenty seven cubic feet. Because of that, a shallow layer can cover many square feet. A thick layer covers less area with the same yardage. The calculator converts any entered depth to feet first. Then it multiplies area by depth. Finally it divides by twenty seven.
Planning Material Before Ordering
Real projects rarely match perfect math. Soil settles. Gravel compacts. Concrete forms may be slightly deeper than planned. Spreading mulch by hand can create uneven spots. Waste percentage helps cover these issues. A small allowance is useful for neat jobs. Larger allowances fit irregular beds, rough ground, and long hauls from the delivery point.
Using Cost and Density Results
Cost per cubic yard helps compare supplier quotes. Bag counts help when bulk delivery is not practical. Truck load estimates show how many hauls may be needed. Density converts yardage into tons. This is helpful for gravel, sand, soil, and stone. Always check the supplier density. Moisture and gradation can change the real weight.
Best Measuring Practice
Measure the area in sections when the shape is not simple. Add each section together. Use inches for thin layers, such as two inches of mulch. Use feet for thick fills and footings. Keep all measurements consistent. Round up material orders when running short would delay work. Keep the final number visible for quotes, invoices, and crew notes.
Common Project Checks
Before buying, compare the calculated yardage with product coverage charts. Check minimum delivery amounts. Confirm whether the supplier sells by loose yard, compacted yard, or ton. For slabs, verify form depth at several points. For landscaping, mark the finished height. These quick checks reduce surprises and make the conversion much more useful. Save notes with the result for later repairs. Reorder decisions become easier for owners, contractors, and delivery teams on repeat projects without remeasuring.
FAQs
How do I convert square feet to cubic yards?
Multiply square feet by depth in feet. Then divide by 27. The result is cubic yards before waste, compaction, or ordering allowances.
Why is depth required?
Square feet only measure surface area. Cubic yards measure volume. Depth changes the flat area into a three dimensional layer.
How many cubic feet are in one cubic yard?
One cubic yard contains 27 cubic feet. This comes from 3 feet × 3 feet × 3 feet.
Can I use inches for depth?
Yes. Enter the depth value and choose inches. The calculator converts inches to feet before calculating cubic feet and cubic yards.
Should I add waste percentage?
Yes for most jobs. Five to ten percent is common for small irregular areas. Larger jobs may need more based on grade, forms, and handling.
What does compaction allowance mean?
Compaction allowance adds extra material for settling or packing. It is useful for gravel, soil, road base, and other loose materials.
Can this estimate concrete?
Yes. Enter slab area and depth. Select concrete, add waste, and use the cost field to estimate order value.
Can this estimate mulch or soil?
Yes. Select mulch, topsoil, compost, or a custom density. Use shallow depths in inches for landscape coverage.
Why does the calculator show tons?
Some suppliers sell gravel, sand, soil, or stone by weight. Tons are estimated from cubic yards and selected material density.
How accurate is the bag count?
The bag count rounds up using the entered bag size. Actual coverage can change with moisture, settling, and how material is spread.
Can I download the result?
Yes. Use the CSV button for spreadsheet data. Use the PDF button for a printable result summary.