Log Weight Calculator: Green Weight by Species and Size

How it works

The log is treated as a cylinder: volume is π ÷ 4 × diameter² × length. Green weight is that volume times the green density of the species.

Green density is the dry wood density (specific gravity × the weight of a cubic foot of water) plus the water still in the wood. The moisture figure is the average of the published heartwood and sapwood values, or whichever is published for species where only one is listed.

Volume (ft³) = π ÷ 4 × (D in ÷ 12)² × L ft Green density = SG × 62.4 × (1 + MC ÷ 100) Weight = volume × green density SG = green specific gravity; MC = green moisture content, % of oven-dry weight

Worked example

A single white oak log, 20 inches in diameter and 8 feet long:

Green density = 0.6 SG × 62.4 × (1 + 71% ÷ 100) = 64 lb/ft³
Volume = π ÷ 4 × (20 ÷ 12)² × 8 = 17.45 ft³ per piece
Weight = 17.45 × 64 = 1,117 lb per piece

Input	Value
Species	White oak
Average diameter (inside bark)	20 in
Length	8 ft
Number of pieces	1

Result	Value
Estimated green weight	1,117 lb
Volume	17.45 ft³
Green density	64 lb/ft³

Green density by species

Species	Specific gravity	Green moisture (%)	Green density (lb/ft³)
White oak	0.6	71	64
Northern red oak	0.56	75	61
Sugar (hard) maple	0.56	69	58.9
Silver maple	0.44	78	48.7
White ash	0.55	45	49.8
Green ash	0.53	58	52.3
Yellow birch	0.55	73	59.4
Paper birch	0.48	81	54.1
Black walnut	0.51	82	57.8
Black cherry	0.47	58	46.3
American elm	0.46	94	55.5
Hackberry	0.49	63	49.8
Quaking aspen	0.35	104	44.6
American basswood	0.32	107	41.3
Eastern cottonwood	0.37	154	58.6
Yellow-poplar	0.4	95	48.5
Red pine	0.41	83	46.8
Tamarack	0.49	49	45.6
Douglas-fir (coast)	0.45	76	49.4
Western redcedar	0.31	154	49
Balsam fir	0.33	131	47.5

Show the green density by species table

Species	Specific gravity	Green moisture (%)	Green density (lb/ft³)
White oak	0.6	71	64
Northern red oak	0.56	75	61
Sugar (hard) maple	0.56	69	58.9
Silver maple	0.44	78	48.7
White ash	0.55	45	49.8
Green ash	0.53	58	52.3
Yellow birch	0.55	73	59.4
Paper birch	0.48	81	54.1
Black walnut	0.51	82	57.8
Black cherry	0.47	58	46.3
American elm	0.46	94	55.5
Hackberry	0.49	63	49.8
Quaking aspen	0.35	104	44.6
American basswood	0.32	107	41.3
Eastern cottonwood	0.37	154	58.6
Yellow-poplar	0.4	95	48.5
Red pine	0.41	83	46.8
Tamarack	0.49	49	45.6
Douglas-fir (coast)	0.45	76	49.4
Western redcedar	0.31	154	49
Balsam fir	0.33	131	47.5

Specific gravity from USDA Wood Handbook Table 5-3a; moisture is the average of heartwood and sapwood from Table 4-1. Green density = SG × 62.4 × (1 + moisture).

Assumptions and limits

Freshly cut wood. Logs lose water weight as they season.
Uses the average diameter; measure a tapered log at the middle.
Moisture is the Handbook average of heartwood and sapwood. A small-diameter log is mostly sapwood and can run heavier than shown for species with wet sapwood (aspen, basswood, red pine).
Bark, branches, and foliage are not included. Only species with a published green moisture value are listed.

Common questions

How much does a cubic foot of green oak weigh?

By this method about 61 lb/ft³ for northern red oak and 64 for white oak. Green sugar maple comes out near 59, white ash near 50, and quaking aspen and basswood between 41 and 45.

How much does a log weigh per foot?

Divide the total weight by the length. A 20-inch white oak works out to about 140 lb per foot.

Why does the same species weigh different amounts?

Moisture changes with season and site, and dead, hollow, or rotten wood weighs far less. Weigh a representative piece when the pick is critical.

Sources

USDA Forest Products Laboratory, Wood Handbook: Wood as an Engineering Material (FPL-GTR-282, 2021): Table 5-3a (green specific gravity) and Table 4-1 (average green moisture content, heartwood and sapwood).
Weight of water: 62.4 lb/ft³.
Read them: USDA Wood Handbook, Chapter 5 (specific gravity) · USDA Wood Handbook, Chapter 4 (moisture content)

Updated 2026-09-30