Soil laboratory client checking a report
Confirm the reported fine-earth fractions map to the USDA class.
Enter the same-basis laboratory sand, silt and clay percentages totaling 100%.
Gets the expected class and retains the three input fractions.
USDA Fine-Earth Texture Check
Classify an exact laboratory sand, silt, and clay record into one of the 12 USDA mineral-soil fine-earth texture classes.
Built for Soil Science1 documented formulaFocused single-task workflowPrivate in your browser
Use this result well
A quick decision brief for this specific tool
Inputs that matter
Laboratory sand, silt and clay percentages on one mineral-soil <2 mm fine-earth basis totaling exactly 100%
Output to expect
Entered total, retained three-fraction record and one of the 12 USDA textural-triangle classes
How it works
Applies USDA fine-earth triangle boundaries only; it is not soil-series identification, an engineering classification or a management prescription
- Verify laboratory particle-size method, fraction definitions, rounding and common <2 mm basis; do not mix sieve/hydrometer results, whole-soil percentages or coarse fragments.
- Use the full soil description and qualified soil survey/laboratory guidance for organic materials, gypsum, cemented layers, coarse fragments, engineering behavior, irrigation, drainage or amendments.
Choose your path
Built around the job you need to finish
Classify a valid mineral-soil fine-earth sand/silt/clay record across all 12 USDA textural classes with an exact total check.
Field soil scientist reviewing a boundary sample
Avoid a shortcut classifier that omits legitimate USDA classes.
Use the exact laboratory fractions and compare the result with the official triangle and full pedon description.
Can identify a boundary/classification question without replacing professional description.
Designer seeking engineering behavior
Recognize USDA texture is not USCS/AASHTO or a design parameter.
Use the tool only for fine-earth texture, then obtain required engineering tests and coarse-fragment data separately.
Does not convert a USDA class into bearing, drainage or amendment advice.
Authoritative checks for this tool
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
- Soil Survey ManualUSDA Natural Resources Conservation Service · Official USDA soil-description manual defining the fine-earth fraction and 12 basic mineral-soil textural classes.
- Soil Texture CalculatorUSDA Natural Resources Conservation Service · Official interactive USDA textural-triangle reference for sand, silt and clay percentages totaling 100 percent.
- Soil Survey Laboratory Methods ManualUSDA Natural Resources Conservation Service · Official particle-size analysis methods and reporting context for laboratory fine-earth sand, silt and clay records.
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Reference & details
How it works
Updated August 2026
How it works
Updated August 2026Use One Fine-Earth Basis
All three inputs must be laboratory percentages of the same less-than-2-millimeter mineral fine-earth fraction. Whole-soil percentages and coarse fragments cannot be mixed into the triangle record.
Require a Complete Composition
Sand, silt, and clay must each be between 0 and 100 and total 100.00 percent within a 0.01-point numerical tolerance. The worksheet does not silently normalize an incomplete analysis.
Apply All 12 USDA Classes
The classifier evaluates the USDA textural-triangle boundaries for sand, loamy sand, sandy loam, loam, silt loam, silt, sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay, and clay.
Updated: August 2026
Example Scenarios
Check that a three-fraction particle-size record maps to the reported USDA fine-earth class.
Enter unrounded laboratory fractions and compare a near-boundary result with the official triangle and laboratory reporting convention.
Use the class as one part of a complete soil description that separately records coarse fragments, horizons, structure, consistence, mineralogy, and other properties.
Common Mistakes to Avoid
Common Mistakes to Avoid
Entering fractions that do not share the same basis
Use one laboratory analysis of the less-than-2-millimeter mineral fraction. Do not combine whole-soil sand with fine-earth silt and clay.
Treating USDA texture as an engineering or management verdict
USCS/AASHTO classification, bearing, shrink-swell, drainage, irrigation, and amendment decisions require additional tests and site context.
FAQ
The triangle represents a complete three-part composition of sand, silt, and clay in the same fine-earth fraction.
No. Correct the laboratory basis, rounding, or transcription so the three fractions total 100 percent.
No. Gravel and larger fragments are outside the less-than-2-millimeter fine-earth percentages and must be described separately.
No. Series classification requires complete horizon morphology, landscape, parent material, diagnostic properties, and other evidence.
The basic mineral fine-earth triangle may not be the appropriate standalone description. Use the applicable USDA method and qualified soil-science guidance.
About USDA Fine-Earth Texture Check
This checker applies the full USDA 12-class textural triangle to a complete mineral-soil fine-earth particle-size record. It preserves the entered fractions and rejects incomplete totals instead of guessing or normalizing them.