Dirt Calculator
Estimate how much dirt, fill dirt, topsoil, garden soil, or screened soil you need for landscaping, grading, raised beds, lawn leveling, backfill, drainage areas, and sitework projects. Calculate cubic yards, tons, truckloads, bags, delivery, waste, and total cost in seconds.
Calculate Dirt Needed
Your Dirt Estimate
Formula used:
Practical recommendation:
Quick Formula Box
Area = length × width
Depth in feet = depth in inches ÷ 12
Cubic feet = area × depth in feet
Base cubic yards = cubic feet ÷ 27
Adjusted cubic yards = base cubic yards × (1 + extra allowance %) × (1 + compaction/settling %)
Estimated tons = adjusted cubic yards × tons per cubic yard
Truckloads = ceil(adjusted cubic yards ÷ truck capacity)
Total cost = dirt cost + delivery + spreading labor + tax
Dirt Coverage Reference Table
| Dirt Type | Typical Use | Planning Weight | Depth Guidance | Common Mistake |
|---|---|---|---|---|
| Fill dirt | Raising grade, filling low spots, building subgrade | About 1.0–1.3 tons per cu yd | Use deeper layers with compaction | Using topsoil where structural fill is needed |
| Screened topsoil | Lawns, landscaping, planting areas | About 1.1–1.3 tons per cu yd | 2–6 inches for lawn and landscape work | Not adding extra for settling |
| Garden soil mix | Raised beds, vegetable gardens, flower beds | About 0.9–1.2 tons per cu yd | 6–12 inches or full bed depth | Buying fill dirt instead of planting soil |
| Clay soil | Heavy fill, shaping, compacted areas | About 1.3–1.6 tons per cu yd | Use carefully; drainage may be poor | Ignoring water retention and compaction difficulty |
| Sandy soil | Drainage-friendly fill, blending, light grading | About 1.0–1.2 tons per cu yd | Useful where drainage matters | Assuming it holds shape like clay |
| Compost blend | Soil amendment, garden improvement | About 0.6–0.9 tons per cu yd | 1–3 inches as amendment | Using pure compost as structural fill |
| Lawn leveling soil | Leveling shallow depressions | Varies by blend | Usually 0.25–1 inch per pass | Smothering grass with too much depth at once |
| Raised bed soil | Planter boxes and garden beds | Usually lighter than fill dirt | Fill to bed depth minus mulch space | Forgetting that deep beds need a lot of soil |
| Backfill dirt | Around walls, trenches, and foundations | Depends on material | Compact in lifts where required | Backfilling with poor drainage material |
| Bulk delivery | Large landscape and grading projects | Truck capacity may be weight-limited | Best for 2+ cubic yards | Comparing bag price directly to bulk price |
How to Use the Dirt Calculator
Dirt Calculator Guide
A dirt calculator helps estimate how much soil is needed for landscaping, lawn repair, grading, garden beds, raised beds, fill projects, backfill, and site preparation. Dirt is usually sold by the cubic yard in bulk and by the cubic foot in bags, so the most useful calculation converts your project area and desired depth into cubic feet and cubic yards.
The basic calculation is simple: multiply length by width to get square feet, convert your depth from inches to feet, multiply area by depth, and divide by 27 to convert cubic feet into cubic yards. Real-world projects also need an allowance for settling, compaction, uneven grade, spreading loss, and measurement error. This calculator includes those practical adjustments so your estimate is closer to what you should actually order.
What This Dirt Calculator Does
This tool estimates square footage, cubic feet, cubic yards, adjusted cubic yards, estimated tons, truckloads, bag count, dirt material cost, delivery cost, optional spreading labor, tax, and total project cost. It works for fill dirt, screened topsoil, garden soil, compost blends, sandy soil, clay soil, lawn leveling soil, and general landscape soil planning.
To keep the calculator easy for first-time users, the default form only asks for length, width, depth, and dirt type. Advanced Options allow more detailed planning for extra allowance, compaction, truck size, bag size, delivery cost, labor cost, and sales tax. This provides a fast workflow for homeowners while still supporting more detailed estimates for contractors, landscapers, and property managers.
Why Accurate Dirt Estimating Matters
Dirt volume is easy to underestimate because shallow depths spread across large areas add up quickly. A 20 by 12 foot area at 4 inches deep already needs nearly 3 cubic yards before extra allowance. Raised beds, low spots, and backfill areas can require much more soil than expected, especially when settling and compaction are included.
Ordering too little dirt can delay a project and add extra delivery charges. Ordering too much can leave a pile of soil that must be stored, spread, or hauled away. A good estimate helps you compare bulk delivery versus bags, choose the right dirt type, plan labor, and avoid wasted money.
Dirt Calculation Formula Explained
The standard dirt volume formula is:
Cubic feet = length × width × depth in feet
If the area is 20 feet long and 12 feet wide:
20 × 12 = 240 square feet
If the desired depth is 4 inches:
4 ÷ 12 = 0.333 feet
Now calculate cubic feet:
240 × 0.333 = 80 cubic feet
Convert to cubic yards:
80 ÷ 27 = 2.96 cubic yards
If you add 10% extra and 10% settling allowance:
2.96 × 1.10 × 1.10 = 3.58 cubic yards
Cubic Yards vs Bags of Dirt
Bulk dirt is usually best for larger projects. One cubic yard equals 27 cubic feet. If a bag contains 1.5 cubic feet, then one cubic yard equals about 18 bags. For small garden repairs, bags may be convenient. For lawn leveling, raised beds, grading, or fill work, bulk delivery is often easier and more cost-effective.
Bagged soil is cleaner to handle and easier to store, but large projects can require many bags. Bulk soil requires delivery access and a place to dump the load. If you have a narrow driveway, overhead wires, steep access, or limited staging space, confirm delivery requirements before ordering.
Choosing the Right Dirt Type
Fill dirt is usually used for raising grade, filling holes, building subgrade, and shaping land. It is not ideal for planting because it may contain clay, sand, small rocks, and low organic matter. Topsoil is better for lawns and landscape beds because it supports plant growth. Garden soil mixes are often lighter and richer, making them better for raised beds and vegetables.
Compost blends improve soil structure and nutrients but are not meant to be used as structural fill. Clay soil can compact well but may drain poorly. Sandy soil drains better but may not hold shape or nutrients as well. Choosing the wrong dirt can create drainage problems, settling, poor plant growth, or unnecessary cost.
Practical Applications
Homeowner Uses
Contractor and Landscaper Uses
Depth Guidelines
For lawn topdressing, a shallow layer of 0.25 to 0.5 inch is common so grass is not smothered. For lawn repair or new seed, 1 to 3 inches of topsoil may be used depending on the existing soil. For landscape beds, 3 to 6 inches is common when refreshing soil. Raised beds often need 8 to 12 inches or more depending on the bed depth and planting goals.
For fill dirt, depth depends on the grade change. Fill should often be placed and compacted in layers rather than dumped all at once. Deep fill areas may need proper compaction, drainage, and sometimes professional evaluation, especially near structures, retaining walls, foundations, driveways, or patios.
Common Mistakes to Avoid
A common mistake is entering depth in feet when the calculator expects inches. Another mistake is forgetting that one cubic yard equals 27 cubic feet, not 9 or 12. Many users also forget to add extra material for settling, uneven grade, slopes, and spreading loss.
Another mistake is using planting soil as fill or using fill dirt for garden beds. Fill dirt is usually cheaper but may not support healthy plant growth. Topsoil and garden soil cost more but are better for lawns and planting areas. Compost is useful as an amendment, but too much compost can shrink as it decomposes and may not provide stable grade.
Delivery planning is also important. Bulk dirt is heavy, and trucks need safe access. A full load may not be possible in wet conditions or on soft driveways. Ask suppliers where they can dump the soil, whether the price includes delivery, and whether the truck is limited by volume or weight.
Expert Recommendations
Measure carefully and use the average depth. If your yard is uneven, take several depth measurements and use a realistic average. Add 10% for most projects and more for rough grading or compacted fill. For planting areas, choose screened topsoil or a garden blend. For structural filling, choose appropriate fill material and compact in lifts.
For large projects, order bulk soil rather than bags. For small planters or patch repairs, bagged soil may be more convenient. If the project is near a foundation, retaining wall, drainage route, driveway, patio, or utility line, consider professional guidance before adding large amounts of dirt.
Conclusion
This dirt calculator estimates cubic yards, cubic feet, tons, truckloads, bags, delivery, labor, tax, and total cost for dirt and soil projects. It is useful for homeowners, gardeners, landscapers, contractors, and property managers who need quick planning numbers. Final quantities should be verified with actual site measurements, supplier recommendations, soil type, compaction needs, delivery access, and local pricing.