Your Raised Bed Soil Needs
Enter dimensions above to calculate volume and get the perfect soil mix breakdown.
Enter dimensions above to calculate volume and get the perfect soil mix breakdown.
Our raised bed soil calculator gives you precise cubic feet and cubic yards instantly. Combined with proven US soil mix recipes from university extension services and experienced gardeners, you’ll never overbuy or underfill your beds again.
Native garden soil often compacts in raised beds and drains poorly. A good mix provides excellent drainage, aeration, nutrients, and microbial life — leading to healthier roots and higher yields.
1. Simple 50/50 Mix (easiest & most recommended)
50% high-quality topsoil + 50% compost
2. Mel’s Mix (Square Foot Gardening)
⅓ compost + ⅓ vermiculite + ⅓ peat moss or coco coir
3. 3-Way Blend (for better drainage)
~33% topsoil + 33% compost + 33% coarse sand or perlite
4. Enhanced Mix (for heavy feeders)
50% topsoil + 30% compost + 20% organic matter (aged leaves, worm castings, etc.)
• 6–8 inches → Leafy greens (lettuce, spinach, kale)
• 12 inches → Most vegetables (tomatoes, peppers, beans)
• 18+ inches → Root crops (carrots, potatoes), tomatoes, and large plants
Most gardeners choose 12–18 inches for maximum versatility.
4×4 ft → 16 cu ft (0.6 cubic yards)
4×8 ft → 32 cu ft (1.2 cubic yards)
3×6 ft → 18 cu ft (0.67 cubic yards)
4×8 ft at 18″ depth → 48 cu ft (1.8 cubic yards)
Tip: Bulk delivery is usually much cheaper above 1 cubic yard.
1. Measure length × width in feet
2. Convert depth from inches to feet (divide by 12)
3. Multiply: Length × Width × Depth = Cubic Feet
4. Divide by 27 = Cubic Yards
Our calculator does all this automatically and breaks down the mix for you.
Multiply length × width × depth (in feet) to get cubic feet. Divide by 27 for cubic yards. Our tool does the math for you and shows the exact mix breakdown.
The simplest and most effective is the 50/50 mix: 50% topsoil + 50% compost. It balances drainage, nutrients, and cost perfectly for most US climates.
12–18 inches is ideal for most vegetables. Use 6–8 inches for leafy greens and 18+ inches for root vegetables or large plants like tomatoes.
Bulk soil (delivered by the yard) is 3–5 times cheaper for beds larger than 4×8 ft. Bagged soil is convenient only for very small projects.
No liner is needed. Many gardeners add cardboard or hardware cloth for weed/rodent control, but excellent drainage in the soil mix is far more important.
Divide total cubic feet by 1.5 and round up. Our calculator shows the exact bag estimate automatically.
Designed specifically for American gardeners using real-world measurements and proven mix recipes. Whether you’re filling one 4×8 bed or planning an entire backyard garden, this tool helps you buy exactly the right amount of soil — saving time, money, and back pain.