Skip to content
UseCalcNow
Agriculture

Log Weight Calculator — Estimate Timber Load Weight

Calculate log weight by diameter, length, and wood species density. Essential for logging transport, crane lift planning, and sawmill operations.

About This Calculator

Logging operators, truck drivers, and sawmill managers all need to know how much logs weigh before moving them. This calculator estimates log weight using the small-end diameter, log length, and green wood density for the species you are working with. The results help you stay within legal load limits, choose the right lifting equipment, and plan sawmill throughput with real numbers instead of guesswork.

The Formula Behind This Calculator

The formula treats the log as a cylinder. First, it converts the diameter from inches to feet and calculates the cross-sectional area (pi times radius squared). Then it multiplies by the log length to get volume in cubic feet. The volume is multiplied by the species' green density in pounds per cubic foot to get total weight. For example, a 16-inch diameter, 16-foot long pine log at 38 lb/ft³ density yields roughly 8.4 cubic feet of volume and weighs about 320 lb.

Understanding the math helps you verify results and make better decisions for your project.

How to Use

  1. 1Measure the diameter at the small end of the log, inside the bark, in inches.
  2. 2Enter the log length in feet from butt to top cut.
  3. 3Look up the green density for your wood species from the reference table below.
  4. 4Enter the density value and read the estimated weight in pounds and tons.

When to Use

  • Planning truck loads to stay within legal DOT weight limits
  • Selecting cranes, skidders, or loaders with enough lift capacity
  • Estimating sawmill daily throughput based on log weight
  • Pricing standing timber or delivered logs by weight
  • Calculating payload for logging trailers and forwarding equipment

Tips

  • Always measure at the small end for a conservative weight estimate.
  • Green wood can weigh 50–100% more than seasoned dry wood depending on the species.
  • Hardwoods like hickory and white oak can reach 55–58 lb/ft³ green, while cedar sits around 24 lb/ft³.
  • Bark adds roughly 10–15% to total log weight, so remove it from the diameter measurement for accuracy.
  • Check your state's axle weight limits before dispatching a loaded log truck on public roads.

How Log Weight Is Calculated

Log weight depends on two factors: the volume of wood and the density of that wood. Volume comes from treating the log as a cylinder — you take the diameter, calculate the cross-sectional area, and multiply by length. Density varies widely by species, from lightweight cedar at around 24 lb/ft³ to dense hickory pushing 55 lb/ft³ green.

The calculator uses the small-end diameter (inside bark) because that is the standard forestry measurement point. This gives a conservative estimate since the actual log is wider at the butt end. For logs with significant taper, averaging the butt and top diameters gives a more accurate result.

In professional logging, weight scaling has largely replaced board-foot scaling in many regions because truck scales are faster and more accurate. The weight-to-volume conversion factors are well established for commercial species in each region, and most mills pay by ton rather than by the thousand board feet.

Wood Species Density Reference Table

Green density values for common North American tree species, based on USDA Forest Service data. Use these values in the wood density field above for the most accurate weight estimate for your logs.

Softwoods: Eastern white pine 22–29 lb/ft³, Southern yellow pine 38–42, Douglas fir 33–38, Eastern hemlock 29–34, Sitka spruce 27, Western red cedar 24, balsam fir 26, loblolly pine 42.

Hardwoods: Red oak 48, white oak 47–55, sugar maple 44, hickory 55–58, yellow birch 44, American elm 35, black cherry 38, black walnut 40, quaking aspen 26, cottonwood 28 lb/ft³.

Green Weight vs Dry Weight: What Changes

Freshly cut trees carry significant water weight. In living trees, moisture content by weight can exceed 100% for softwoods and 80% for hardwoods. As wood dries, it loses water and becomes significantly lighter. A red oak log that weighs 48 lb/ft³ green might drop to 38 lb/ft³ after air-drying for a full year.

Kiln drying removes even more moisture, bringing hardwoods down to 6–8% moisture content for furniture use. At that point, a board may weigh half its green weight. For transport planning, always use green density unless you are moving kiln-dried lumber — in which case the lumber calculator is the more appropriate tool.

Firewood sellers often price by the cord, but buyers care about actual wood weight. A cord of green hickory weighs over 5,500 lb while a cord of dry aspen weighs barely 2,000 lb. The density field in this calculator lets you compare those scenarios directly by switching the input value.

Log Scaling: Doyle, Scribner, and International Rules

Log scaling rules estimate how many board feet of lumber can be cut from a log. The three main systems — Doyle, Scribner, and International 1/4-inch — each use different kerf assumptions and taper adjustments. Doyle is the simplest but tends to underestimate small logs and overestimate large ones.

Weight scaling bypasses these formulas entirely. Mills weigh each truckload on a certified scale and convert to board feet using a species-specific conversion factor. For example, one ton of green Southern pine logs typically yields 180–220 board feet of usable lumber.

If you need to estimate board footage from a log before cutting, the board foot calculator handles that calculation separately. The weight-to-board-foot conversion varies by species, log quality, and sawmill efficiency, so local experience and historical recovery data are the best guides.

Transportation and Equipment Load Planning

Federal bridge law sets gross vehicle weight limits for interstate highways at 80,000 lb for a standard 5-axle semi. State roads may allow higher limits with permits. A loaded log truck carrying 30 tons of timber needs a tractor and trailer rated for that payload, plus a safety margin for braking and stability.

Crane and loader operators also need accurate weight estimates. A knuckleboom loader rated at 20,000 lb lift capacity at full reach cannot safely pick up a single large oak log that weighs 3,000 lb at that distance. Log weight estimates prevent equipment damage, tipped trailers, and worksite accidents.

For residential tree removal, the same math applies on a smaller scale. A personal tractor with a 3,000 lb winch needs to know if that storm-damaged maple log will exceed its pulling capacity before the cable snaps. Running the numbers before rigging up is cheap insurance compared to a damaged machine or injured operator.

Sawmill Recovery and Yield Planning

Sawmill operators track recovery rate — the percentage of log volume that becomes sellable lumber. A well-run hardwood mill might recover 35–45% of log volume as grade lumber, with the rest going to pallet stock, chips, sawdust, and bark mulch. Softwood mills typically see higher recovery rates of 50–65%.

Log weight directly affects daily throughput. If a mill processes 100 tons of logs per day at 40% recovery, that is roughly 40 tons of lumber out the door. Knowing the incoming weight lets managers schedule kiln capacity, drying time, and grading crews ahead of the actual sawing.

Once logs are milled into dimensional lumber, the framing calculator helps convert those boards into wall assemblies, while the wall framing calculator breaks down stud counts and plate lengths for specific building dimensions. For outdoor projects, the decking calculator handles board spacing and material estimates.

Workplace Safety in Logging Operations

Logging remains one of the most dangerous occupations in the United States, with a fatal injury rate roughly 30 times the national average across all industries. Accurate weight estimation reduces risk by ensuring chainsaw operators, equipment handlers, and truck drivers work within safe load boundaries every shift.

OSHA requires employers to assess job hazards and provide training for all logging operations. Knowing log weight is part of that hazard assessment — a log that appears manageable can exceed equipment limits when green hardwood density is factored in. Choker cables, slings, and rigging all have rated capacities that must not be exceeded during lifting.

Downstream wood processing carries its own risks. The board and batten calculator helps plan exterior siding projects, while the mulch calculator estimates landscaping material from bark and wood chips. Both start with logs that came off a landing where safety was the first priority.

Timber Pricing and Carbon Accounting

Timber is often sold by the ton in the US South and by the thousand board feet (MBF) in other regions. Converting between weight and volume requires knowing the species mix and average density of the load. Delivered log prices in 2025 ranged from $25–55 per ton for pine pulpwood and $45–80 per ton for pine sawtimber in southern timber markets.

Carbon accounting has added another reason to track log weight. Forest carbon is measured in metric tons of CO2 equivalent, and roughly half of dry wood biomass is stored carbon. A 10-ton load of pine logs contains about 4.5 tons of stored carbon, equivalent to 16.5 tons of CO2 removed from the atmosphere over the tree's lifetime.

For small-scale builders planning a project with milled lumber, the DIY shed cost calculator can estimate the total material investment for common outbuildings. Weight and cost estimation together give a complete picture of what those logs are worth.

FAQ

What is green wood density?

Green density refers to the weight of freshly cut wood with its natural moisture content intact. It is higher than dry density because the wood cells are still saturated with water.

How do I find the density value for my tree species?

The USDA Forest Service publishes green weight tables for North American species. Common values: Southern yellow pine 38–42 lb/ft³, red oak 48 lb/ft³, Douglas fir 38 lb/ft³, cedar 24 lb/ft³, hickory 55 lb/ft³.

Does this calculator account for taper?

No, it uses the small-end diameter only. Logs with significant taper will weigh more than the estimate since the actual volume is larger. For high-taper logs, measure diameter at both ends and use the average.

Can I use this for firewood weight?

Yes. Cut firewood rounds match the same cylinder shape. Use the green density if freshly cut, or reduce the density by 30–50% if the wood has been seasoning for 6 months or more.

How much does a logging truck carry?

A standard semi-trailer logging truck in the US legally hauls 25–30 tons of logs per load, depending on state weight limits and axle configuration. This calculator helps you figure out how many logs fill that payload.

Related Calculators