Enter your bed or pot dimensions. Get cubic feet, cubic yards, and exact bag count in under 5 seconds. No app, no account, no guessing.
From dimensions to bag count in under 5 seconds. No app download, no account, no waiting.
Take length, width, and depth with a tape measure. Use any unit — feet, inches, centimetres, or metres. The calculator converts automatically.
⏱ 2 minutes to measureChoose rectangle, circle, triangle, cylinder, trapezoid, or L-shape. Enter your dimensions in the fields. Each shape has its own formula applied automatically.
⏱ Optional — 10 secondsThe calculator returns cubic feet, cubic yards, and exact bag counts for 1 cu ft, 1.5 cu ft, and 2 cu ft bags — everything you need at the nursery.
⏱ Under 5 secondsNo switching between tools or doing manual conversions. Everything a gardener needs — in one result.
The standard unit for bagged soil in the US. Every bag label shows cubic feet — this number tells you exactly how many bags to grab.
The unit used for bulk soil delivery. If your volume is over 1 cubic yard, ordering bulk from a landscape supplier saves 60–70% versus bags.
Results for three common bag sizes — 1, 1.5, and 2 cubic feet. Always rounded up so you never run short mid-project.
Potting mix in Europe and South Asia is sold by litre. The litre result lets you buy the right volume without any manual conversion.
5 reasons this tool beats every other online soil calculator.
Most online calculators limit free use or push you to sign up. This calculator has no paywall. Every calculation is free, every time.
No login, no email, no personal data shared. Open the tool, enter your dimensions, get your answer.
Rectangle, circle, triangle, cylinder, trapezoid, and L-shape. Most calculators only handle rectangles — this one covers every real garden shape.
Enter dimensions in feet, inches, centimetres, or metres. The calculator converts automatically — no manual unit math needed.
Most calculators give cubic yards only. This one gives bag counts for 3 common bag sizes so you know exactly what to buy at the nursery.
Works in Chrome, Safari, and Firefox on any device. No installation, no storage used on your phone.
The calculator works across all common garden bed and container shapes.
Simple geometry applied instantly — no rounding errors, no manual conversion.
When you enter your dimensions and click Calculate, the tool converts all measurements to feet, applies the correct geometric formula for your selected shape, and returns the volume in cubic feet.
Converting to cubic yards divides by 27. Converting to litres multiplies by 28.32. Bag counts divide by each standard bag size and round up — so you always have enough, never too little.
Accuracy is exact to 2 decimal places. The only variable the calculator cannot account for is soil settling — which is why we add a 10% buffer recommendation to every result.
Rectangle, circle, triangle, trapezoid, cylinder — each has a different formula applied automatically.
Inches, feet, cm, metres — all converted to feet before calculation for precision.
Never rounds down. Always gives you enough bags — never the amount that leaves you short.
Results accurate to 0.01 cubic feet — precise enough for any garden project.
Guessing and manual calculation both lead to the same problem — wrong bag count.
| Method | ZonedGarden Calculator | Manual Formula | Guessing by Eye | Generic Online Calc |
|---|---|---|---|---|
| Exact cubic feet result | ✓ Free | ✓ | ✗ | ✓ |
| Bag count output | ✓ Free | ✗ | ✗ | Sometimes |
| 6 shape types | ✓ Free | ✓ if you know the formula | ✗ | ✗ (rectangle only) |
| Metric + Imperial units | ✓ Free | ✗ manual convert | ✗ | Rarely |
| No account required | ✓ | ✓ | ✓ | Often requires signup |
| Result in under 5 seconds | ✓ | ✗ takes 2–5 mins | ✓ (wrong result) | ✓ |
| Litre output for metric users | ✓ Free | ✗ | ✗ | ✗ |
Depth is the number most gardeners get wrong. Use this table before calculating volume.
| Plant Type | Min Depth | Recommended | Notes |
|---|---|---|---|
| Salad greens & herbs | 4 in (10 cm) | 6 in (15 cm) | Lettuce, basil, cilantro — ideal for window boxes and shallow troughs |
| Most vegetables | 8 in (20 cm) | 12 in (30 cm) | Tomatoes, peppers, beans, cucumbers — standard raised bed depth |
| Root vegetables | 12 in (30 cm) | 18 in (45 cm) | Carrots, parsnips, beets — need deep, loose soil to develop fully |
| Perennial flowers | 8 in (20 cm) | 12 in (30 cm) | Hostas, daylilies, coneflowers — established roots spread wide |
| Small shrubs | 12 in (30 cm) | 18 in (45 cm) | Lavender, rosemary, roses — need drainage below root zone |
| Annual flowers | 6 in (15 cm) | 8 in (20 cm) | Petunias, marigolds, pansies — shallow but need good drainage |
| Lawn top-dressing | 0.5 in (1 cm) | 1 in (2.5 cm) | Over-seeding and levelling — thin layer across large area |
These 5 habits prevent the most common soil-buying mistakes.
Measure length and width from the inside edge of the bed frame, not the outside. The inside dimension is the soil area.
Measure the actual depth you plan to fill — not the total frame height. Leaving 2 inches below the top is standard.
Fresh soil settles 5–15% after watering. Always buy 10% more than the calculator shows to account for this.
If adding large drainage rocks to the bottom of a deep bed, subtract that layer's volume from your total before calculating soil.
The calculator always rounds bag counts up. Never round down — one short bag means a second trip to the nursery.
7 questions gardeners ask most before calculating soil volume.
7 types of gardeners and professionals rely on this tool daily.
Building new raised beds, refilling settled beds each spring, or setting up a first container garden.
Calculating potting mix for indoor planters — checking soil volume before repotting houseplants.
Scaling up from 2 beds to 20. Calculating total soil volume across all beds before ordering a bulk truckload.
Botany, horticulture, and environmental science coursework and school garden projects.
Accurate soil cost quotes for clients. Avoid under-estimates that eat into project margins on large landscape jobs.
Planning multiple garden beds at a new property. Calculate total volume across all beds, place one bulk order.
Setting up school or community garden beds. Exact calculations for grant applications and budget requests.
