Soil Mechanics & Lab Tests
USCS Soil Classifier
Classify soil samples according to ASTM D2487 standard: coarse-grained, fine-grained, organic soils, dual symbols (GW-GM, SP-SM, etc.), and Casagrande plasticity chart.
USCS Soil Classifier
Classify soil samples according to ASTM D2487 standard: coarse-grained, fine-grained, organic soils, dual symbols (GW-GM, SP-SM, etc.), and Casagrande plasticity chart.
Inputs
1. Soil Fraction Percentages
Sum: 0%2. Gradation & Atterberg Limits
3. Advanced Settings & Overrides
Assume non-plastic fines if Atterberg limits are missing for coarse soils (e.g. GW-GM).
Classify as ML or MH if Atterberg limits are completely missing for fine soils.
Assume soil is organic (O) if organic content > 5% and LL (Oven Dry) is not provided.
Used by the Organic % Fallback if LL (Oven Dry) is unavailable.
Results
Enter gravel, sand, and fines percentages (summing to 100%) above, or click a Demo Preset at the top to classify the soil sample.
Theory and formulae
USCS Classification Criteria
About this calculator
This free uscs soil classifier calculator runs entirely in your browser: what you enter is never uploaded. Use the calculation steps and the theory section to check the working, and print a calculation sheet with the inputs, results and formulae for your records.
Methods and references: ASTM D2487, ASTM D4427.
Topics: uscs, soil classification, astm d2487, atterberg limits, casagrande, plasticity chart.
Engineering notice: Results are for preliminary estimation, screening and education. All inputs and outputs must be independently verified by a qualified professional engineer before use in any design or construction decision. Read the full disclaimer
Disclaimer
This calculation sheet was generated with Geotechnical Toolbox for preliminary estimation, screening, educational and verification purposes only. Geotechnical engineering involves site-specific ground conditions and uncertainty. All inputs, methods, results and figures must be independently checked and approved by a qualified Professional Engineer (P.Eng. / PE) before being relied on for design, construction or any safety-critical decision. Results reflect the values entered at the time of printing. The author and site accept no liability for errors, omissions or damages arising from their use.
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