Timber Volume Calculator
Estimate timber volume for sawn lumber, beams, planks, boards, sleepers, square posts, and round logs. Calculate cubic feet, cubic meters, board feet, quantity, waste allowance, weight estimate, and material cost in a simple, mobile-friendly tool.
Calculate Timber Volume
Your Timber Volume Estimate
Formula used:
Practical recommendation:
Quick Formula Box
Sawn timber volume = length × width × thickness × quantity
Round log volume = π × (diameter ÷ 2)² × length × quantity
Cubic feet to cubic meters = cubic feet × 0.0283168
Cubic feet to board feet = cubic feet × 12
Board feet = thickness(in) × width(in) × length(ft) ÷ 12 × quantity
Final volume = measured volume × (1 + waste percentage)
This calculator uses geometric volume. Forestry log scaling rules such as Doyle, Scribner, and International 1/4-inch log rule estimate recoverable lumber, not exact cylinder volume, and may produce different results.
Timber Volume Reference Table
| Measurement | Formula / Conversion | Best For | Planning Note | Common Mistake |
|---|---|---|---|---|
| Cubic feet | Length(ft) × width(ft) × thickness(ft) | General timber volume and weight estimates | Useful for beams, planks, posts, and material storage | Mixing inches and feet without conversion. |
| Cubic meters | Cubic feet × 0.0283168 | International timber trade and metric estimates | Common for forestry, sawmills, and bulk timber | Rounding too early in the calculation. |
| Board feet | T(in) × W(in) × L(ft) ÷ 12 | North American lumber pricing | Represents a 1 in × 12 in × 12 in board volume | Using nominal size instead of actual size when needed. |
| Round log volume | π × radius² × length | Geometric log volume | Good for approximate solid log volume | Confusing geometric volume with sawmill recovery. |
| Waste allowance | Measured volume × waste % | Cuts, kerf, defects, trimming, milling | 10% is a practical default for many jobs | Buying exact volume with no cutting allowance. |
| Wood weight | Cubic feet × density | Handling, delivery, storage, transport | Density varies widely by species and moisture | Using dry weight for green timber. |
| Price estimate | Volume × unit price | Budgeting and comparing suppliers | Match the calculator price mode to supplier pricing | Mixing price per board foot and price per cubic meter. |
How to Use the Timber Volume Calculator
Timber Volume Calculator Guide
A timber volume calculator helps estimate the amount of wood in boards, planks, beams, posts, sleepers, slabs, and logs. Timber volume is useful for buying lumber, comparing supplier prices, planning transport, estimating weight, preparing sawmill orders, managing woodworking projects, and calculating material needs for construction or agricultural use.
Timber can be measured in several ways. Sawn timber is commonly calculated as rectangular volume using length, width, and thickness. Logs are often estimated using a cylindrical volume formula or a log scaling rule. Lumber pricing may use board feet, cubic feet, cubic meters, linear feet, or price per piece. This calculator brings those common conversions into one simple tool.
What This Timber Volume Calculator Does
This tool estimates timber volume in cubic feet, cubic meters, and board feet. It also calculates volume per piece, total volume, waste-adjusted volume, approximate weight, and estimated material cost. It works for sawn lumber, timber beams, planks, boards, sleepers, posts, square stock, and round logs.
The default workflow uses only four main inputs: length, width or diameter, thickness, and quantity. A simple timber type selector changes the formula between rectangular timber and round logs. Advanced options include unit choices, waste allowance, price mode, price, and wood density. This keeps the calculator fast enough for first-time users while still useful for real-world material planning.
Why Timber Volume Matters
Timber volume affects cost, shipping, storage, yield, and waste. If you underestimate volume, you may run short during cutting or milling. If you overestimate, you may spend more than needed or end up storing heavy material that may warp, split, or dry unevenly. Accurate volume estimates also help compare prices between suppliers who quote in different units.
For example, one supplier may quote hardwood in board feet, another may quote beams by cubic foot, and an international seller may quote round logs by cubic meter. A timber volume calculator makes it easier to compare those offers by converting the same material into multiple units.
Timber Volume Formula Explained
For rectangular timber such as boards, beams, planks, and posts, the formula is:
Volume = length × width × thickness × quantity
All dimensions must be in the same unit before multiplying. If length is in feet and width and thickness are in inches, the calculator converts width and thickness to feet first. The result is cubic feet. It then converts cubic feet to cubic meters and board feet.
For board feet, the common formula is:
Board feet = thickness(in) × width(in) × length(ft) ÷ 12 × quantity
A board foot is a volume equal to a board 1 inch thick, 12 inches wide, and 12 inches long. Since 1 cubic foot contains 12 board feet, the calculator also converts cubic feet to board feet by multiplying by 12.
For round logs, the geometric volume formula is:
Log volume = π × radius² × length × quantity
This gives approximate solid cylinder volume. Real logs taper, have bark, defects, sweep, oval shape, and milling loss, so sawmill recovery may be lower than geometric volume.
Board Feet, Cubic Feet, and Cubic Meters
Board feet are widely used for lumber pricing in North America, especially for hardwoods and rough lumber. Cubic feet are useful for general volume, storage, weight, and engineered calculations. Cubic meters are common in forestry, sawmills, export markets, and metric countries.
When comparing prices, be careful to compare the same unit. A price per board foot is not the same as a price per cubic foot. Since one cubic foot equals 12 board feet, a $4 per board foot board equals $48 per cubic foot before considering grade, drying, surfacing, or waste.
Waste Allowance and Milling Loss
Waste allowance is important because real timber projects rarely use every cubic inch of material. Cutting, trimming, saw kerf, defects, knots, cracks, checking, wane, planing, jointing, and milling all reduce usable yield. For clean sawn boards, 5% to 10% may be enough. For rough logs, slabs, defects, or complex woodworking, 15% to 20% may be more realistic.
For logs, geometric volume is not the same as recoverable lumber volume. Sawmill yield depends on log diameter, taper, saw kerf, log rule, grade, defects, sawing pattern, and target board sizes. Use this calculator as a volume estimator, then apply a realistic recovery factor if you are estimating finished lumber output.
Practical Applications
Construction and Buying Uses
Woodworking and Forestry Uses
Common Mistakes to Avoid
A common mistake is mixing units. If length is in feet but width and thickness are in inches, you must convert before multiplying. Another mistake is using nominal dimensions when actual dimensions are needed. A nominal 2×6 board may not actually measure 2 inches by 6 inches, especially after surfacing.
Users also often forget moisture content. Green timber can be much heavier than dry timber, and it may shrink as it dries. Weight estimates based on average density are only approximate because species, moisture, and treatment can change weight significantly.
For logs, a common mistake is assuming cylinder volume equals finished lumber volume. Logs have bark, taper, defects, slab loss, saw kerf, and milling waste. If you are estimating saleable boards from logs, use a log rule or sawmill recovery estimate in addition to geometric volume.
Expert Recommendations
Measure carefully and record units before calculating. Use actual dimensions for sawn lumber when possible. Add realistic waste for cuts, defects, trimming, and milling. When buying expensive hardwood, confirm whether the supplier prices by gross board feet, net board feet, surfaced dimensions, rough dimensions, or per piece.
For timber transport, use conservative weight estimates, especially for green logs and dense hardwoods. For structural beams, volume is only a quantity estimate; strength, grade, species, moisture, treatment, span, and code requirements must be verified separately. For log purchases, clarify whether measurement includes bark and which log rule or scaling method is being used.
Conclusion
This timber volume calculator gives a fast, practical estimate for cubic feet, cubic meters, board feet, waste allowance, weight, and cost. It works for sawn timber, beams, planks, boards, posts, sleepers, square stock, and round logs. For best results, use accurate dimensions, choose the correct shape, match units to supplier pricing, include realistic waste, and verify grading, moisture, recovery, and structural requirements before buying or building with timber.