/// Amendment volume planner

Compost Calculator

Use the compost calculator to turn measured treatment area and entered application depth into cubic feet, cubic yards, or cubic meters, then add only the allowance you choose. It does not prescribe an amendment depth or material density. Soil test recommendations, compost properties, blending, settling, bag coverage, bulk increments, delivery, and site access require separate verification.

Content reviewed Jul 16, 2026 · Source records reviewed through Jul 15, 2026

01

Compost area and depth

Enter the area and amendment depth recommended for the soil and use. Compost composition, maturity, and bulk density vary.

ftExample starting measurement — replace it with your field measurement.
ftExample starting measurement — replace it with your field measurement.
inExample starting measurement — replace it with your field measurement.
%Required — enter a project-specific planning value and verify it before ordering. ProjectQty does not apply an unsupported default.
USDOptional — enter your current local price per cubic yard.
View current estimate

/// Answer-first planning notes

What compost volume matches my measured area and application depth?

What compost volume matches my measured area and application depth checkpoints
Planning inputCalculation roleLandscape check
Treatment areaSets the amended footprintMeasure only intended beds
Application depthTurns area into compost volumeUse the project or soil recommendation
AllowanceAdds handling or contour volumeKeep supplier increments separate

/// Formula & field notes

How this compost estimate works

FormulaCompost volume = treatment length × width × applied depth × (1 + waste %), converted to bulk cubic units.

Worked example

A 20 ft × 10 ft bed amended 3 in deep contains about 1.85 yd³ before waste and about 2.04 yd³ with 10% allowance.

/// Source trail

Data & assumptions

Every source has a declared scope. A reference can support a conversion or product assumption without turning this estimate into a supplier quote.

National Institute of Standards and Technology · Primary evidenceNIST Guide to the SI, Appendix B: Conversion Factors

Exact international-foot to meter conversion; U.S. survey-foot conversion is explicitly outside this claim.

Effective 2025-08-18 · Reviewed 2026-07-15 · Next review 2027-07-15
NOAA National Geodetic Survey · Prequalified fallbackThe DSDATA Format, Appendix D: U.S. Survey Foot vs International Foot

Independent confirmation that one international foot equals exactly 0.3048 meters; U.S. survey-foot conversion remains distinct.

Effective 2025-06-10 · Reviewed 2026-07-15 · Next review 2027-07-15

/// Common questions

Compost calculator FAQ

What should I verify before ordering compost?

Confirm field dimensions and appropriate application depth and supplier volume unit against the exact product or supplier information. ProjectQty shows the assumptions so you can replace planning defaults before ordering cubic yards or cubic meters.

How does waste affect the compost estimate?

Waste is applied after the base geometry is calculated and before discrete packages or pieces are rounded up. Use a higher allowance for complex layouts, cuts, pattern matching, breakage, or uncertain field dimensions.

Is this compost result a professional design?

No. It is a quantity-planning result. Soil testing, nutrient management, compost quality, salinity, contaminants, and crop suitability require project-specific guidance.