Interactive raised bed calculator
Enter bed size. Get soil volume, bags, cost, and a shopping list.
Default example: one 4×8×12 in bed, 10% settling, and 2 ft³ bags. Results update automatically as inputs change.
More planners: mix, containers, spacing, top-off, depth, cost, multi-bed, shapes
Raised Bed Soil & Planting Calculator
4×8 Raised Bed 8 Inches Soil Calculator
Calculate soil volume and bags for a 4×8 raised bed filled 8 inches deep.
Preset: raised bed dimensions
Formula: 4 × 8 × 8/12 = 21.33 ft³
Worked example: A 4×8 bed at 8 inches deep needs about 21.33 ft³ before settling.
Adjust the live inputs above before copying the shopping list, printing the result, or buying material.
4×8 bed at 8 inches
These rows use one 4×8 bed, 0 in freeboard, 10% settling allowance, and 2 ft³ bags. Change the live calculator for other assumptions.
| Depth | Before settling | With 10% | 2 ft³ bags | Planning note |
|---|---|---|---|---|
| 8 in | 21.33 ft³ | 23.47 ft³ / 0.87 yd³ | 12 | Moderate shallow depth: workable for many smaller crops, but limited for deep-rooted or long-season vegetables. |
Quick copy: 8 in: 21.33 ft³ before settling; 23.47 ft³ with 10% settling; 0.87 yd³; about 12 × 2 ft³ bags.
What to verify
- Measuring outside dimensions instead of inside fill dimensions.
- Forgetting freeboard below the bed rim.
- Buying bags without checking the package volume.
Page-specific notes
- Eight inches can work for many shallow crops but is limited for larger vegetables.
Disclaimer
BedSoil results are planning estimates for buying and mixing soil. They are not agricultural, engineering, pest, disease, fertilizer, or crop-yield advice. Check product labels, local material quality, drainage, bed construction, climate, and crop variety before purchasing materials.