Free Online Timber Log Volume & Weight Calculator

Whether you are a forest owner, truck driver, log buyer, or firewood enthusiast, estimating the precise volume (cubic meters) and total mass (tons) of wood logs is critical for transparent trade and safe logistics. The QTP Timber Log Volume & Weight Calculator provides a rapid, client-side solution to find the exact wood mass and cylinder cubic capacity without installing heavy software or using external hidden APIs.

How to Use the Calculator

• Step 1: Choose Your Measurement Method. Select “Single Diameter” if you only measure the log’s mid-diameter or top-diameter. Choose “Diameter on Both Ends” for precise calculations based on the two distinct cross-sectional ends of a tapered log.
• Step 2: Enter Dimensions. Input the total length of the timber piece in meters (m), along with the target diameter in centimeters (cm).
• Step 3: Select Wood Species (Optional). If you need to estimate the weight for trucking or shipping limitations, pick the appropriate wood type (e.g., fresh pine, green oak, or seasoned firewood) to auto-apply commercial timber density scales.
• Step 4: Set the Quantity. Multiply your current calculations instantly across matching logs by scaling up the count field.
• Step 5: Export. Click “Calculate” to view results live and hit “Download Results (.txt)” to instantly export a clean summary document.

Log Volume Math & Density Standards

This tool uses precise geometric formulas universally recognized in wood measurement models:

• Single Diameter Rule: Built upon the standard cylindrical formula V = pi * r^2 * L, where r is the calculated radius from your input diameter and L represents length.
• Smalian’s Tapered End Rule: Uses both cross-sections to find an average area multiplied by the longitudinal distance: V = ((A1 + A2) / 2) * L, making it far more reliable for logs with significant natural tapering.
• Mass Dynamics: Density fluctuates heavily based on sap and moisture saturation. Fresh green softwood often reaches 850 kg/m³, while dry seasoned varieties drop closer to 500 kg/m³, changing shipping weights dramatically.