Proctor Compaction Test Calculator
Enter mold measurements and wet soil weights for each compaction point to get dry unit weight, plot the curve, and find OMC and MDD.
Test Configuration
4-inch mold ≈ 944 cm³
For ZAV curve (typical 2.60–2.75)
Compaction Data Points
| # | Wet Soil Mass (g) | Moisture Content (%) | Dry Unit Weight (kN/m³) |
|---|
Optimum Moisture Content (OMC)
—
%
Maximum Dry Density (MDD)
—
kN/m³
Compaction Curve
Blue dots = data points | Blue line = fitted curve | Dashed = Zero Air Voids (ZAV)
Calculated Values
| Point | Moisture Content (%) | Wet Unit Weight (kN/m³) | Dry Unit Weight (kN/m³) |
|---|
Summary
Enter mold measurements and wet soil weights for each compaction point to get dry unit weight, plot the curve, and find OMC and MDD.
How it works
- Select Standard or Modified Proctor test type.
- Enter the mold volume and the number of data points (typically 4–6).
- For each point, enter the wet soil mass and moisture content percentage.
- The calculator converts wet density to dry unit weight using the formula: γd = γwet / (1 + w).
- The compaction curve is plotted and the peak is identified as the optimum moisture content (OMC) and maximum dry density (MDD).
- Zero-air-voids (ZAV) curve is overlaid using specific gravity for reference.
Use cases
- Geotechnical lab analysis of soil compaction characteristics.
- Field quality control for earthwork, embankments, and road subgrade.
- Determining compaction specifications for construction projects.
- Academic study and verification of Proctor test calculations.
- Comparing Standard vs Modified Proctor compaction results.
- Cross-checking hand-calculated lab data against plotted curves.
Frequently Asked Questions
Last updated: 2026-07-24 ·
Reviewed by Nham Vu