Fill Dirt Calculator

This calculator makes one quantity chain visible: entered length, width, and fill depth become a finished geometric volume; the selected adjustment then produces a loose-volume planning result; the selected density model produces a displayed tonnage estimate. That is valuable for tracing a material conversation with a supplier or contractor, because the inputs are not hidden behind a generic coverage claim.

A quantity result does not identify suitable fill, certify density, select a compaction method, approve a building pad, solve surface or subsurface drainage, or design a foundation or retaining wall. The USDA NRCS Soil Survey Manual describes the range of soil properties and interpretations that exist beyond a simple material name. Keep those project decisions outside this calculator.

Use this page after the project has defined the finished grade and material question. The yardage guide explains the core unit conversion; this page explains the particular values and limits of this calculator.

Start with a small plan and section sketch. On the plan, identify the limits where the selected material is intended to go. On the section, record existing grade, target grade, and the depth that applies across that zone. A sloped yard, stepped area, trench backfill, driveway subbase, and retaining-wall material zone should not be combined into one rectangle merely because they are near each other.

For an irregular area, break the work into named shapes with consistent dimensions and depth. Enter each line separately, retain the intermediate cubic-yard results, and add only after checking that no area was omitted or counted twice. If the depth varies continuously, use a documented average for that specific zone rather than a convenient number for the whole property.

The calculation first converts each entered measurement to feet. It then uses the standard rectangular-volume relationship:

The current NIST Handbook 44 includes the measurement tables used to check these unit conversions. The cubic-yard conversion is exact; errors normally come from mixing inches and feet or entering a depth that does not match the finished zone.

Next, the interface applies the percentage selected in its adjustment dropdown:

The label says compaction, but in the code this is a simple percentage increase applied to volume. It is not a test, a field-density result, or a recommendation that one percentage belongs to every project.

The calculator offers 0%, 5%, 10%, and 15% choices to show how a selected volume increase changes the material quantity. Do not read those menu labels as a design rule for lawns, foundations, retaining walls, trenches, or any other project. The FHWA's geotechnical reference material on compaction describes compaction as a material- and condition-dependent engineering and quality-control subject. A shopping calculation cannot substitute for that work.

If a supplier, drawing, or responsible project professional has given a documented loose-to-finished relationship for the selected material, enter the matching adjustment and retain the source with the worksheet. If no such information exists, do not turn the calculator's preset into a claim that the result will settle, bear load, drain, or perform in a particular way.

Keep fill volume distinct from excavation volume too. The hole created by an excavation can include overdig, unsuitable material removal, working room, or grade changes that do not match the specified imported-material zone. Use the Excavation Calculator for the removed-material geometry and this page for a separately defined fill zone.

The displayed tonnage is not a universal conversion. This calculator multiplies the loose cubic yards by a fixed interface density associated with the selected material label. Natural variation, moisture, gradation, contaminants, product processing, and the supplier's sales unit can change real weight. Ask the supplier how the exact material is quoted and obtain their stated unit weight if a cubic-yard-to-ton conversion is needed.

The three load cards are even more limited: they divide the loose volume by 7.5, 12, and 18 and show decimals. They do not round up, reserve a truck, establish a truck's capacity, or account for legal payload, axle limits, delivery access, route, site conditions, or supplier minimums. Use them to compare your volume with an actual carrier conversation, not as a delivery instruction.

If the finished surface needs planting soil, use the Topsoil Calculator for that distinct layer. If the project specifies aggregate rather than soil, calculate it separately with the Gravel Calculator and follow the actual material documentation.

A correct cubic-yard calculation is only the beginning of a fill-material conversation. A building pad, foundation, retaining wall, drainage feature, utility trench, slope, or low-spot repair may involve material selection, water, geotechnical conditions, local requirements, and construction controls that this tool cannot evaluate. The retaining-wall material takeoff guide is an example of why each material zone must remain separate.

Before ordering, compare the worksheet with the latest plan, supplier product description, stated order unit, delivery access, and responsible project requirements. Keep a note of the measured finished volume, the exact adjustment used, the density source, and every rounding or quote change. Report an issue or unclear result if the calculator's math, sources, or explanation needs correction.