Fill Volume Calculator: Free Online Fill Volume Calculator
Use our free fill volume calculator to determine how much fill material you need for site grading, leveling, or building up a low area. Built for site contractors and landscapers, it converts a length, width, and average fill depth into the area and volume of fill required, in cubic yards.
How to use this calculator.
- Enter the area length. Measure the longer dimension of the area to be filled, in feet.
- Enter the area width. Measure the shorter dimension, in feet.
- Enter the average fill depth. If the area isn't uniformly deep, estimate the average depth across the whole footprint, in feet.
- Review your results. The calculator returns total area and fill volume in cubic yards.
- Add for compaction. Order 15–25% more loose fill than the calculated volume to account for settlement once it's compacted.
How do you calculate fill material volume for site work?
This calculator uses a straightforward area-times-depth approach: it finds the footprint area, then multiplies by the average fill depth and converts cubic feet to cubic yards.
Area (sq ft) = Length (ft) × Width (ft)
Volume (cu yd) = Length (ft) × Width (ft) × Depth (ft) ÷ 27
Where:
- Length and Width: The footprint dimensions of the area being filled, in feet.
- Depth: The average fill depth needed to bring the area up to finished grade, in feet. This is the difference between proposed grade and existing grade.
- 27: The conversion factor from cubic feet to cubic yards (3 ft × 3 ft × 3 ft = 27 cu ft per cu yd).
Example calculation.
Let's calculate the fill needed to level a low section of a building pad before grading.
Scenario: The low area measures 100 ft by 50 ft, with an average fill depth of 2 ft needed to reach finished grade.
- Calculate the area: 100 ft × 50 ft = 5,000 sq ft
- Calculate volume in cubic feet: 5,000 sq ft × 2 ft = 10,000 cu ft
- Convert to cubic yards: 10,000 cu ft ÷ 27 = 370.4 cu yd
- Add 20% for compaction: 370.4 cu yd × 1.20 = 444.4 cu yd of loose fill to order
Result: This area needs approximately370 cubic yards of compacted fill, so plan to order closer to 445 cubic yards of loose material once compaction settlement is factored in.
Tips from the field.
- Order 15–25% extra for compaction. Loose fill settles significantly once compacted — 100 loose cubic yards typically compacts down to 75–85 cubic yards.
- Compact in 6–8 inch lifts. Placing fill too thick and rolling only the surface leaves weak, uncompacted material underneath that settles unevenly over time.
- Know your material's swell factor before hauling.Clay swells 20–30% and sand 10–15% when excavated, which affects truck counts if you're moving cut material into the fill area rather than importing it.
- Target 95% of maximum dry density for structural fill.Anything supporting a foundation, slab, or pavement needs this level of compaction; landscape fill can typically get away with less.
- Grid the site for irregular areas. Break large or uneven areas into a grid, estimate fill depth at each point, and sum the sections for a more accurate total than a single average depth.
Disclaimer: This calculator provides estimates for planning purposes only. Actual fill requirements vary based on subgrade conditions, compaction method, material type, and site survey accuracy. For structural fill or load-bearing applications, consult a licensed civil engineer. PavementCalculator.com assumes no liability for material overages or shortages.
Cost, price, and density figures on this page reflect approximate U.S. averages as of August 2026 and vary by region, supplier, and material availability.
Frequently asked questions.
How do I calculate fill volume for a site?
Grid method: Divide the site into a grid (typically 50 ft × 50 ft squares). At each grid point, calculate: Fill Depth = Proposed Grade - Existing Grade (positive = fill, negative = cut). Average fill depth × Grid area = Fill volume per grid. Sum all grid volumes for total fill. This calculator uses a simplified area × depth approach for single-area estimates.
How do I calculate fill volume?
Calculate the volume of the void: length × width × average depth (in feet) ÷ 27 = cubic yards. For irregular areas, divide into sections and sum the volumes. Add 15-25% for compaction: loose fill compresses significantly when compacted.
What is the swell factor in fill calculations?
Swell factor is how much soil expands when excavated. Clay swells 20-30%, sand 10-15%, gravel 5-10%. When calculating fill, account for compaction: loose fill compresses 15-25%. 100 loose cu yd of clay compacts to ~70-80 cu yd.
What is compaction and why does it matter?
Compaction reduces air voids in soil, increasing density and load-bearing capacity. Uncompacted fill settles over time, causing cracks in structures above. Compact fill in 6-8 inch lifts to 95% of maximum dry density for structural applications.
How much does fill dirt settle after compaction?
Loose fill settles 15-25% when compacted. 100 loose cu yd compacts to 75-85 cu yd. Always order 15-25% more loose fill than your target compacted volume. Our calculator accounts for this automatically.