Log Weight Calculator
Estimate what a log weighs before you lift, load, or mill it. Enter the mid-log diameter in inches and length in feet, choose the species, and get freshly cut (green) weight in pounds, US tons, and kilograms.
Example: with Diameter, mid-log (in) 16 · Length (ft) 10 · Species (green weight) Red oak (~63 lb/cu ft) → Green weight: 880 lb (399 kg).
- In US tons0.44 US tons
- Log volume13.96 cu ft at 63 lb/cu ft green
Computed by the calculator below using its default values. Change any input to see your own numbers.
Weight = cylinder volume × green density. Freshly cut hardwood logs carry so much water that a 16 in × 10 ft red oak log runs near 900 lb.
Why green logs weigh so much
A freshly felled log is often half water by weight. Green red oak runs about 63 lb per cubic foot versus roughly 44 lb/cu ft after air-drying — the water alone in a big log can outweigh a person. That is why the species list here uses green densities: the number that matters when you are dragging, loading, or trailering a log is its weight the day it comes down.
The calculator treats the log as a cylinder using the mid-length diameter, which is Huber's classic approximation for a tapered stem. Measure diameter inside the bark at the middle of the log if you can; using the butt-end diameter on a strongly tapered log can overstate weight by 15% or more.
How it’s calculated
Volume = π × (diameter ÷ 24)² × length, with diameter in inches and length in feet, giving cubic feet (mid-diameter cylinder, Huber's formula). Weight = volume × green density from USDA Forest Products Laboratory Wood Handbook moisture and specific-gravity data, rounded to common industry chart values (red oak 63 lb/cu ft, white pine 36, etc.). Tons at 2,000 lb; kg at 0.45359237 per lb.
Green densities are averages — moisture content, season, and individual trees swing real weight ±10–15%, so leave margin when sizing equipment.
Green weight of a 16 in × 10 ft log
| Species | Green density | Log weight |
|---|---|---|
| Hickory | 64 lb/cu ft | ≈ 894 lb |
| Red oak | 63 lb/cu ft | ≈ 880 lb |
| Hard maple | 56 lb/cu ft | ≈ 782 lb |
| Southern yellow pine | 53 lb/cu ft | ≈ 740 lb |
| Douglas-fir | 39 lb/cu ft | ≈ 545 lb |
| Eastern white pine | 36 lb/cu ft | ≈ 503 lb |
Computed with π × (16/24)² × 10 = 13.96 cu ft × green density; densities per Wood Handbook-based industry charts.
Common mistakes
- Measuring diameter at the flared butt end — use the mid-log diameter, or the average of both ends, or the estimate runs heavy.
- Using dry lumber weights for a fresh log: green wood weighs 30–60% more than air-dried stock of the same species.
- Entering circumference as diameter — divide tape-around-the-log readings by 3.14 first.
- Ignoring bark and crotches on yard trees; hardware-laden or soaked urban logs can exceed chart weight.
Frequently asked questions
How do you calculate the weight of a log?
Weight = π × (diameter in inches ÷ 24)² × length in feet × green density. A 16 in × 10 ft red oak log: 13.96 cubic feet × 63 lb/cu ft ≈ 880 lb.
How much does a 20 ft log weigh?
Depends on girth and species. At 18 in diameter, a 20 ft red oak log is about 35.3 cubic feet × 63 ≈ 2,230 lb; the same log in white pine is roughly 1,270 lb.
Why use green weight instead of dry weight?
Because you handle logs green. Fresh-cut wood is loaded with water — red oak drops from about 63 to 44 lb per cubic foot as it dries — and winches, arches, and trailers must carry the green number.
Can my truck or trailer handle a big log?
Check the numbers, not the eyeball: a single 24 in × 10 ft oak log runs near 2,000 lb, which is the entire payload of many half-ton pickups. Compare log weight against payload and hitch ratings, and remember loaders tip well below their rated lift at full reach.