Garden Calculator
Calculate garden square footage for beds, lawns, soil, mulch, seed, edging, and landscaping materials.
Garden Bed Calculator
All Square Foot Calculators
Choose a specialized calculator for your specific project type.
Garden Square Footage Formula
Calculate your garden bed or lawn area using the shape that best matches your layout. Most garden beds are rectangular, but raised circular beds and triangular corner beds are also common.
Knowing the exact area of your garden helps you calculate how many bags of mulch, topsoil, fertilizer, or seeds you need. Coverage rates are typically listed in sq ft per bag on the product label.
Soil and Mulch Coverage
To find how many bags you need: divide the garden area by the coverage per bag. For a 2-inch deep mulch layer over 200 sq ft, you need roughly 200 ÷ 12 = 1.11 cubic yards or about 17 bags (2 cu ft each).
How to Measure Your Garden
- Walk the perimeter: Mark the boundaries of each bed or lawn section.
- Choose the shape: Select rectangle, circle, or triangle for each section.
- Measure dimensions: Use a measuring tape or wheel for accuracy.
- Sum the sections: Add the areas of all sections for the total garden footprint.
Garden Coverage Reference
| Material | Coverage per Bag | Notes |
|---|---|---|
| Mulch (2 cu ft bag) | ~12 sq ft at 2-inch depth | 2-inch depth standard |
| Top Soil (1 cu ft bag) | ~6 sq ft at 2-inch depth | Amend 2–4 inches deep |
| Grass seed | 250–500 sq ft/lb | Varies by grass type |
| Fertilizer | 5,000–10,000 sq ft/bag | Read label for rate |
Frequently Asked Questions
Measure the length and width in feet, then multiply. A 6 × 12 ft raised bed = 72 sq ft. For circular beds, use π × r².
A 2 cu ft bag covers about 12 sq ft at 2-inch depth. Divide your garden area by 12 to get the number of bags. A 200 sq ft garden needs roughly 17 bags.
Calculate volume: length × width × depth (all in feet). A 4 × 8 ft bed, 1 ft deep = 32 cu ft = about 1.19 cubic yards. One cubic yard = 27 cubic feet.
Divide the garden into simpler shapes (rectangles, triangles, semicircles). Calculate each area separately, then add them together for the total square footage.
A beginner vegetable garden is typically 100–200 sq ft. An experienced gardener may cultivate 400–800 sq ft. A large market garden can exceed 5,000 sq ft.