Lumber Dimensions and board actual size chart

A board is named for its rough sawn size, not its finished one. A 2x4 does not measure 2 inches by 4 inches, and a 1x4 in MDF is not the same thickness as a 1x4 in poplar. Below is the real milled size of every board we stock, listed by species.

Quick answers Nominal vs actual Edge profiles Full chart 2x sizes 1x sizes 5/4x sizes WindsorONE FAQ

Stack of milled trim boards in several species showing different thicknesses

The sizes people ask for most, answered

Actual milled dimensions, thickness by width.

2x4 actual size

1 1/2" x 3 1/2"

standard. Ours: 1 7/16"

2x6 actual size

1 1/2" x 5 1/2"

standard. Ours: 1 7/16"

2x8 actual size

1 1/2" x 7 1/4"

standard. Ours: 1 1/4"

1x4 actual size

13/16" x 3 1/2"

most species. See table for all

1x6 actual size

13/16" x 5 1/2"

most species. See table for all

1x2 actual size

13/16" x 1 1/2"

most species. See table for all

Nominal size versus actual size

Nominal size is the trade name, such as 1x4 or 2x6. It refers to the rough sawn dimension of the board before it was surfaced.

Actual size is what arrives and what you cut. It is smaller, because surfacing the board smooth on four sides removes material.

Two rules cover almost everything. Width loses 1/2 inch on nominal sizes under 8 inches and 3/4 inch at 8 inches and above, which is why a 1x6 is 5 1/2 inches but a 1x8 jumps to 7 1/4 inches rather than 7 1/2 inches.

Thickness is the one that surprises people, because it depends on the material rather than the size. An MDF 1x board and a poplar 1x board are not the same thickness even though both are sold as 1x. If you are choosing between materials, our boards range lists every option we carry.

Tape measure across a board showing its true measured width

Edge profiles and what the codes mean

The Profile column in every table on this page describes how a board has been surfaced and how its long edges are finished. It has nothing to do with size, but it changes how the board takes paint, how the edge reads once installed, and which face you show. On our product pages this is the Edge Profile attribute.

Surfacing is how many faces and edges have been planed smooth. The digits in the code count them: S4S is four surfaces, S2S2E is two sides plus two edges, S1S2E is one side plus two edges.

An eased edge is the long corner of the board broken to a small radius, roughly 1/32 to 1/16 inch, rather than left square. It holds paint better, because a sharp corner tends to leave a thin paint film that wears through first. It also survives handling and transport better. A square edge is crisper and is usually what you want for stain grade work or a deliberately modern detail.

Code	Stands for	Faces	Long edges	What it suits
S4S	Surfaced four sides	Both planed smooth	Both planed smooth and left square	Stain grade work, and any detail where a sharp arris is part of the look
S2S2E	Surfaced two sides, two edges	Both planed smooth	Both eased	Painted trim, where two clean faces are wanted but a softened edge helps the paint film
S1S2EWindsorONE sells this as Eased All Edges	Surfaced one side, two edges	One planed smooth, the other left textured	Both eased	Reversible boards. Choose the face you show on site, smooth or textured
n/aas it appears in the tables above	No edge profile specified	Varies with the mill run. Ask before you order if the edge matters to the detail		Framing and utility work, where the edge is not seen

S1S2E and S4S are the same net size in the same nominal. Choosing between them is a finish decision, not a dimensional one.

Milled profiles

A few boards carry a shaped profile rather than a plain surfaced one. These are milled to lock together or to throw a shadow line, so the face you see is not always the width of the board.

Profile	What it is	Where it goes
T&G V-groove	Tongue and groove with a chamfer worked on each edge, so the joint reads as a fine V line	Ceilings, feature walls, wainscot
T&G beaded ceiling	Tongue and groove with a bead milled beside the joint, which disguises the seam between boards	Porch ceilings, wainscot, traditional interiors
V-rustic	An overlapping profile with a V joint, milled so the boards shed water	Exterior cladding and interior feature walls
Thermory cladding	Thermally modified timber in a cladding profile. Heat treatment improves stability and rot resistance without chemicals	Exterior cladding

Tongue and groove widths are coverage, not board width. The tongue disappears into the next board, so the face you actually see is narrower than the piece you are holding. That is why the T&G knotty alder shows 5 3/8 inch at 1x6 and 3 1/8 inch at 1x4, rather than 5 1/2 inch and 3 1/2 inch. Work your material takeoff from the coverage figure, not the nominal.

Full board size chart

Every size we stock, with the exact milled dimension for each species. Pick a thickness class, then a species to highlight its row.

Thickness

Species

Nominal	Species	Profile	Thickness	Width	Actual size
2x2	WindsorONE Protected16ft, square section	S1S2E	1 7/16"	1 7/16"	1 7/16" x 1 7/16"
2x4	Douglas Fir	n/a	1 7/16"	3 1/2"	1 7/16" x 3 1/2"
2x4	Poplarthickest 2x we stock	S4S	1 3/4"	3 1/2"	1 3/4" x 3 1/2"
2x4	WindsorONE Protected	S4S	1 7/16"	3 1/2"	1 7/16" x 3 1/2"
2x4	WindsorONE Protected16ft & 20ft	S1S2E	1 7/16"	3 1/2"	1 7/16" x 3 1/2"
2x4	Primed FJ Cedar16ft & 20ft	S4S	1 7/16"	3 1/2"	1 7/16" x 3 1/2"
2x6	WindsorONE Protected	S4S	1 7/16"	5 1/2"	1 7/16" x 5 1/2"
2x6	WindsorONE Protected16ft & 20ft	S1S2E	1 7/16"	5 1/2"	1 7/16" x 5 1/2"
2x6	Primed FJ Cedar16ft & 20ft	S4S	1 7/16"	5 1/2"	1 7/16" x 5 1/2"
2x8	MDF	n/a	1 1/4"	7 1/4"	1 1/4" x 7 1/4"
2x8	WindsorONE Protected	S4S	1 7/16"	7 1/4"	1 7/16" x 7 1/4"
2x8	WindsorONE Protected16ft & 20ft	S1S2E	1 7/16"	7 1/4"	1 7/16" x 7 1/4"
2x10	WindsorONE Protected16ft & 20ft	S1S2E	1 7/16"	9 1/4"	1 7/16" x 9 1/4"
2x12	MDFunprimed	n/a	1 1/4"	11 1/4"	1 1/4" x 11 1/4"
2x12	WindsorONE Protected16ft & 20ft	S1S2E	1 7/16"	11 1/4"	1 7/16" x 11 1/4"

2x board actual sizes

2x is where our stock differs most from what people expect. Standard construction 2x lumber is 1 1/2 inch thick. Ours is surfaced trim grade rather than framing lumber, so it measures differently.

Worth knowing before you order. We do not stock a 1 1/2 inch 2x board in any width from 2x4 to 2x12. Our 2x range is surfaced trim grade, so it runs 1 7/16 inch, with MDF at 1 1/4 inch and poplar at 1 3/4 inch. If you are matching existing framing, measure first.

2x2 actual size

A 2x2 measures 1 1/2" x 1 1/2" in standard construction lumber. The 2x2 boards we stock are surfaced trim grade and measure 1 7/16".

Species	Profile	Actual size
WindsorONE Protected16ft, square section	S1S2E	1 7/16" x 1 7/16"

Shop this size: buy 2x2 boards.

2x4 actual size

A 2x4 measures 1 1/2" x 3 1/2" in standard construction lumber. The 2x4 boards we stock are surfaced trim grade and measure 1 7/16" and 1 3/4".

Species	Profile	Actual size
Douglas Fir	n/a	1 7/16" x 3 1/2"
Poplarthickest 2x we stock	S4S	1 3/4" x 3 1/2"
WindsorONE Protected	S4S	1 7/16" x 3 1/2"
WindsorONE Protected16ft & 20ft	S1S2E	1 7/16" x 3 1/2"
Primed FJ Cedar16ft & 20ft	S4S	1 7/16" x 3 1/2"

Shop this size: buy 2x4 boards and Poplar.

2x6 actual size

A 2x6 measures 1 1/2" x 5 1/2" in standard construction lumber. The 2x6 boards we stock are surfaced trim grade and measure 1 7/16".

Species	Profile	Actual size
WindsorONE Protected	S4S	1 7/16" x 5 1/2"
WindsorONE Protected16ft & 20ft	S1S2E	1 7/16" x 5 1/2"
Primed FJ Cedar16ft & 20ft	S4S	1 7/16" x 5 1/2"

Shop this size: buy 2x6 boards.

2x8 actual size

A 2x8 measures 1 1/2" x 7 1/4" in standard construction lumber. The 2x8 boards we stock are surfaced trim grade and measure 1 1/4" and 1 7/16".

Species	Profile	Actual size
MDF	n/a	1 1/4" x 7 1/4"
WindsorONE Protected	S4S	1 7/16" x 7 1/4"
WindsorONE Protected16ft & 20ft	S1S2E	1 7/16" x 7 1/4"

Shop this size: buy 2x8 boards and MDF.

2x10 actual size

A 2x10 measures 1 1/2" x 9 1/4" in standard construction lumber. The 2x10 boards we stock are surfaced trim grade and measure 1 7/16".

Species	Profile	Actual size
WindsorONE Protected16ft & 20ft	S1S2E	1 7/16" x 9 1/4"

Shop this size: buy 2x10 boards.

2x12 actual size

A 2x12 measures 1 1/2" x 11 1/4" in standard construction lumber. The 2x12 boards we stock are surfaced trim grade and measure 1 1/4" and 1 7/16".

Species	Profile	Actual size
MDFunprimed	n/a	1 1/4" x 11 1/4"
WindsorONE Protected16ft & 20ft	S1S2E	1 7/16" x 11 1/4"

Shop this size: buy 2x12 boards and MDF.

1x board actual sizes

1x boards are the workhorse trim size. They are where species makes the biggest difference to thickness, so this is the class most worth checking before you cut.

1x2 actual size

A 1x2 measures 1 1/2" wide. Thickness depends on species: 11/16", 13/16", and 3/4", with 13/16" the most common.

Species	Profile	Actual size
MDF	n/a	11/16" x 1 1/2"
Poplar	S4S	13/16" x 1 1/2"
FJ Poplar Primed	S4S	13/16" x 1 1/2"
Alder	S4S	13/16" x 1 1/2"
Knotty Alder	S4S	13/16" x 1 1/2"
Northern Red Oak	S4S	13/16" x 1 1/2"
Hard Maple	S4S	13/16" x 1 1/2"
White Oakplain sawn	S4S	13/16" x 1 1/2"
WindsorONE Protected	S4S	3/4" x 1 1/2"
WindsorONE Protected	S1S2E	3/4" x 1 1/2"
Sage FJPnon-standard width	S4S	11/16" x 1 5/8"
Sage Flexper ft, non-standard width	S4S	11/16" x 1 5/8"

Exception: Sage FJP is 1 5/8" wide and Sage Flex is 1 5/8" wide, rather than the 1 1/2" everything else measures.

Shop this size: buy 1x2 boards, MDF, and Poplar.

1x3 actual size

A 1x3 measures 2 1/2" wide. Thickness depends on species: 11/16", 13/16", 3/4", and 23/32", with 13/16" the most common.

Species	Profile	Actual size
MDF17ft	n/a	11/16" x 2 1/2"
Poplar	S4S	13/16" x 2 1/2"
FJ Poplar Primed	S4S	13/16" x 2 1/2"
Alder	S4S	13/16" x 2 1/2"
Knotty Alder	S4S	13/16" x 2 1/2"
Northern Red Oak	S4S	13/16" x 2 1/2"
Hard Maple	S4S	13/16" x 2 1/2"
White Oakplain sawn	S4S	13/16" x 2 1/2"
WindsorONE Protected	S4S	3/4" x 2 1/2"
WindsorONE Protected	S1S2E	3/4" x 2 1/2"
Sage FJP	S4S	23/32" x 2 1/2"

Shop this size: buy 1x3 boards, MDF, and Poplar.

1x4 actual size

A 1x4 measures 3 1/2" wide. Thickness depends on species: 11/16", 13/16", 3/4", 23/32", and 5/8", with 13/16" the most common.

Species	Profile	Actual size
MDF17ft	n/a	11/16" x 3 1/2"
MDF17ft	S4S	11/16" x 3 1/2"
Poplar	S4S	13/16" x 3 1/2"
FJ Poplar Primed	S4S	13/16" x 3 1/2"
Alder	S4S	13/16" x 3 1/2"
Knotty Alderthinner than 1x2/1x3 knotty alder	S4S	3/4" x 3 1/2"
Northern Red Oak	S4S	13/16" x 3 1/2"
Hard Maple	S4S	13/16" x 3 1/2"
White Oakplain sawn	S4S	13/16" x 3 1/2"
Douglas Fir	n/a	11/16" x 3 1/2"
Clear Pine	n/a	3/4" x 3 1/2"
WindsorONE Protected16ft & 20ft	S4S	3/4" x 3 1/2"
WindsorONE Protected16ft & 20ft	S1S2E	3/4" x 3 1/2"
Sage FJP	S4S	23/32" x 3 1/2"
Knotty Alder	T&G beaded ceiling	5/8" x 3 1/8"

Exception: the tongue and groove knotty alder covers 3 1/8", rather than the 3 1/2" everything else measures.

Shop this size: buy 1x4 boards, MDF, and Poplar.

1x5 actual size

A 1x5 measures 3/4" thick in every species we stock. Width is 4 5/8" in most, and 4 1/2" in WindsorONE Protected.

Species	Profile	Actual size
WindsorONE Protected	S4S	3/4" x 4 1/2"
FJ Poplar Primednon-standard width	S4S	3/4" x 4 5/8"
Knotty Aldernon-standard width	T&G V-groove	3/4" x 4 5/8"

Shop this size: buy 1x5 boards.

1x6 actual size

A 1x6 measures 5 1/2" wide. Thickness depends on species: 11/16", 13/16", 3/4", and 23/32", with 13/16" the most common.

Species	Profile	Actual size
MDF	n/a	11/16" x 5 1/2"
MDF	S4S	11/16" x 5 1/2"
Poplar	S4S	13/16" x 5 1/2"
FJ Poplar Primed	S4S	13/16" x 5 1/2"
Alder	S4S	13/16" x 5 1/2"
Knotty Alder	S4S	3/4" x 5 1/2"
Northern Red Oak	S4S	13/16" x 5 1/2"
Hard Maple	S4S	13/16" x 5 1/2"
White Oakplain sawn	S4S	13/16" x 5 1/2"
Douglas Fir	n/a	11/16" x 5 1/2"
Clear Pine	n/a	3/4" x 5 1/2"
WindsorONE Protected16ft & 20ft	S4S	3/4" x 5 1/2"
WindsorONE Protected16ft & 20ft	S1S2E	3/4" x 5 1/2"
Sage FJP	S4S	23/32" x 5 1/2"
MDF	V-rustic	11/16" x 5 1/2"
Knotty PineSC only	Thermory cladding	3/4" x 5 1/2"
Knotty Alder	T&G beaded ceiling	3/4" x 5 3/8"

Exception: the tongue and groove knotty alder covers 5 3/8", rather than the 5 1/2" everything else measures.

Shop this size: buy 1x6 boards, MDF, and Poplar.

1x8 actual size

A 1x8 measures 7 1/4" wide. Thickness depends on species: 11/16", 13/16", 3/4", and 23/32", with 13/16" the most common.

Species	Profile	Actual size
MDF	n/a	11/16" x 7 1/4"
MDF	S4S	11/16" x 7 1/4"
Poplar	S4S	13/16" x 7 1/4"
FJ Poplar Primed	S4S	13/16" x 7 1/4"
Alderedge glued	S4S	13/16" x 7 1/4"
Knotty Alder	S4S	3/4" x 7 1/4"
Northern Red Oak	S4S	13/16" x 7 1/4"
Hard Maple	S4S	13/16" x 7 1/4"
White Oakplain sawn	S4S	13/16" x 7 1/4"
Douglas Fir	n/a	11/16" x 7 1/4"
Clear Pine	n/a	3/4" x 7 1/4"
WindsorONE Protected16ft & 20ft	S4S	3/4" x 7 1/4"
WindsorONE Protected16ft & 20ft	S1S2E	3/4" x 7 1/4"
Sage FJP	S4S	23/32" x 7 1/4"
MDFnon-standard width	V-rustic	11/16" x 7 1/2"

Exception: the V-rustic MDF is 7 1/2" wide, rather than the 7 1/4" everything else measures.

Shop this size: buy 1x8 boards, MDF, and Poplar.

1x10 actual size

A 1x10 measures 9 1/4" wide. Thickness depends on species: 11/16", 13/16", 3/4", and 23/32", with 13/16" the most common.

Species	Profile	Actual size
MDF	n/a	11/16" x 9 1/4"
Poplar	S4S	13/16" x 9 1/4"
FJ Poplar Primed	S4S	13/16" x 9 1/4"
Alderedge glued	S4S	13/16" x 9 1/4"
Knotty Alder	S4S	3/4" x 9 1/4"
Northern Red Oak	S4S	13/16" x 9 1/4"
Hard Maple	S4S	13/16" x 9 1/4"
White Oakplain sawn	S4S	13/16" x 9 1/4"
Douglas Fir	n/a	11/16" x 9 1/4"
WindsorONE Protected16ft & 20ft	S4S	3/4" x 9 1/4"
WindsorONE Protected16ft & 20ft	S1S2E	3/4" x 9 1/4"
Sage FJP	S4S	23/32" x 9 1/4"

Shop this size: buy 1x10 boards, MDF, and Poplar.

1x12 actual size

A 1x12 measures 11 1/4" wide. Thickness depends on species: 11/16", 13/16", 3/4", and 23/32", with 13/16" the most common.

Species	Profile	Actual size
MDFprimed	n/a	11/16" x 11 1/4"
Poplar	S4S	13/16" x 11 1/4"
FJ Poplar Primed	S4S	13/16" x 11 1/4"
Alderedge glued	S4S	13/16" x 11 1/4"
Knotty Alder	S4S	3/4" x 11 1/4"
Northern Red Oak	S4S	13/16" x 11 1/4"
Hard Maple	S4S	13/16" x 11 1/4"
White Oakplain sawn	S4S	13/16" x 11 1/4"
Douglas Fir	n/a	11/16" x 11 1/4"
WindsorONE Protected16ft & 20ft	S4S	3/4" x 11 1/4"
WindsorONE Protected16ft & 20ft	S1S2E	3/4" x 11 1/4"
Sage FJP	S4S	23/32" x 11 1/4"

Shop this size: buy 1x12 boards, MDF, and Poplar.

1x16 actual size

A 1x16 measures 11/16" x 15" in every species we stock.

Species	Profile	Actual size
MDFunprimed, non-standard width	S4S	11/16" x 15"

Shop this size: buy 1x16 boards and MDF.

5/4x board actual sizes

5/4x, said "five quarter", sits between 1x and 2x. It gives more substance than a 1x without the bulk of a 2x, which is why it is traditional for stair treads, window stools and shelving that has to carry weight.

5/4x3 actual size

A 5/4x3 measures 1 1/16" x 2 1/2" in every species we stock.

Species	Profile	Actual size
WindsorONE Protected	S4S	1 1/16" x 2 1/2"
WindsorONE Protected	S1S2E	1 1/16" x 2 1/2"

Shop this size: buy 5/4x3 boards.

5/4x4 actual size

A 5/4x4 measures 3 1/2" wide. Thickness depends on species: 1" and 1 1/16", with 1 1/16" the most common.

Species	Profile	Actual size
MDF	n/a	1" x 3 1/2"
Knotty Alder	S4S	1" x 3 1/2"
Poplar	S4S	1 1/16" x 3 1/2"
WindsorONE Protected	S4S	1 1/16" x 3 1/2"
WindsorONE Protected	S1S2E	1 1/16" x 3 1/2"
Sage FJP	S4S	1 1/16" x 3 1/2"

Shop this size: buy 5/4x4 boards, MDF, and Knotty Alder.

5/4x5 actual size

A 5/4x5 measures 1 1/16" x 4 1/2" in every species we stock.

Species	Profile	Actual size
WindsorONE Protected	S4S	1 1/16" x 4 1/2"

Shop this size: buy 5/4x5 boards.

5/4x6 actual size

A 5/4x6 measures 5 1/2" wide. Thickness depends on species: 1" and 1 1/16", with 1 1/16" the most common.

Species	Profile	Actual size
MDF	n/a	1" x 5 1/2"
Knotty Alder	S4S	1" x 5 1/2"
Poplar	S4S	1 1/16" x 5 1/2"
VG Fir	n/a	1" x 5 1/2"
WindsorONE Protected	S4S	1 1/16" x 5 1/2"
WindsorONE Protected	S1S2E	1 1/16" x 5 1/2"
Sage FJP	S4S	1 1/16" x 5 1/2"

Shop this size: buy 5/4x6 boards, MDF, and Knotty Alder.

5/4x8 actual size

A 5/4x8 measures 7 1/4" wide. Thickness depends on species: 1" and 1 1/16", with 1 1/16" the most common.

Species	Profile	Actual size
MDF	n/a	1" x 7 1/4"
Poplar	S4S	1 1/16" x 7 1/4"
WindsorONE Protected	S4S	1 1/16" x 7 1/4"
WindsorONE Protected	S1S2E	1 1/16" x 7 1/4"
Sage FJP	S4S	1 1/16" x 7 1/4"

Shop this size: buy 5/4x8 boards, MDF, and Poplar.

5/4x10 actual size

A 5/4x10 measures 1 1/16" x 9 1/4" in every species we stock.

Species	Profile	Actual size
WindsorONE Protected	S4S	1 1/16" x 9 1/4"
WindsorONE Protected	S1S2E	1 1/16" x 9 1/4"
Sage FJP	S4S	1 1/16" x 9 1/4"

Shop this size: buy 5/4x10 boards.

5/4x12 actual size

A 5/4x12 measures 1 1/16" x 11 1/4" in every species we stock.

Species	Profile	Actual size
WindsorONE Protected	S4S	1 1/16" x 11 1/4"
WindsorONE Protected	S1S2E	1 1/16" x 11 1/4"
Sage FJP	S4S	1 1/16" x 11 1/4"

Shop this size: buy 5/4x12 boards.

How each species measures

Thickness is set by the material, not the nominal size, so it is worth knowing how your chosen species behaves across the range.

Species	1x	5/4x	2x
Alder	13/16"	n/a	n/a
Clear Pine	3/4"	n/a	n/a
Douglas Fir	11/16"	n/a	1 7/16"
Hard Maple	13/16"	n/a	n/a
Knotty Alder	5/8, 3/4, and 13/16"	1"	n/a
MDF	11/16"	1"	1 1/4"
Northern Red Oak	13/16"	n/a	n/a
Poplar	13/16"	1 1/16"	1 3/4"
White Oak	13/16"	n/a	n/a
FJ Poplar Primed	3/4 and 13/16"	n/a	n/a
Knotty Pine	3/4"	n/a	n/a
Primed FJ Cedar	n/a	n/a	1 7/16"
Sage FJP	11/16 and 23/32"	1 1/16"	n/a
Sage Flex	11/16"	n/a	n/a
VG Fir	n/a	1"	n/a
WindsorONE Protected	3/4"	1 1/16"	1 7/16"

Board offcuts in MDF, pine, poplar and oak side by side showing grain and colour differences — Thickness differences between species are small on paper but show at every joint, reveal and transition, especially where two materials meet.

WindsorONE Protected net sizes

WindsorONE Protected boards are finger jointed real wood with three coats of acrylic latex primer and a 30 year warranty against rot, insects and mould. They are rated for interior and exterior use.

Two things set them apart from the rest of our range. Thickness does not match standard lumber at 5/4x or 2x, and lengths are 16ft and 20ft rather than 8ft and 16ft.

Nominal	Net size	Edge profiles
1x2	3/4" x 1 1/2"	S1S2E and S4S
1x3	3/4" x 2 1/2"	S1S2E and S4S
1x4	3/4" x 3 1/2"	S1S2E and S4S
1x5	3/4" x 4 1/2"	S4S
1x6	3/4" x 5 1/2"	S1S2E and S4S
1x8	3/4" x 7 1/4"	S1S2E and S4S
1x10	3/4" x 9 1/4"	S1S2E and S4S
1x12	3/4" x 11 1/4"	S1S2E and S4S
5/4x3	1 1/16" x 2 1/2"	S1S2E and S4S
5/4x4	1 1/16" x 3 1/2"	S1S2E and S4S
5/4x5	1 1/16" x 4 1/2"	S4S
5/4x6	1 1/16" x 5 1/2"	S1S2E and S4S
5/4x8	1 1/16" x 7 1/4"	S1S2E and S4S
5/4x10	1 1/16" x 9 1/4"	S1S2E and S4S
5/4x12	1 1/16" x 11 1/4"	S1S2E and S4S
2x2	1 7/16" x 1 7/16"	S1S2E
2x4	1 7/16" x 3 1/2"	S1S2E and S4S
2x6	1 7/16" x 5 1/2"	S1S2E and S4S
2x8	1 7/16" x 7 1/4"	S1S2E and S4S
2x10	1 7/16" x 9 1/4"	S1S2E
2x12	1 7/16" x 11 1/4"	S1S2E

S4S is smooth on all four sides with square edges. S1S2E is smooth on one face and textured on the other, with both long edges eased, so the board can be turned either way. Net size is identical in both. Prime all cuts, including butt joints and miters, unless you are using exterior grade glue.

Common questions

Why is a 2x4 not actually 2 by 4 inches?

A 2x4 is named for its rough sawn size, before it was dried and surfaced. Planing the board smooth on all four sides removes material, so the finished board is smaller. Standard construction 2x4 lumber ends up at 1 1/2 inches by 3 1/2 inches. Our surfaced trim grade 2x4 measures 1 7/16 inches by 3 1/2 inches.

Does actual size change depending on the wood species?

Yes, and this is the part that catches people out. At 1x we stock thicknesses of 11/16 inch, 23/32 inch, 3/4 inch and 13/16 inch depending on the material. MDF is 11/16 inch while poplar, maple, oak and alder are 13/16 inch. Width stays the same across species in almost every case.

Why does the width rule change at 8 inches?

Wider boards shrink more as they dry, so a larger dressing allowance applies. Nominal widths under 8 inches lose 1/2 inch and 8 inches and over lose 3/4 inch. That is why a 1x6 is 5 1/2 inches but a 1x8 is 7 1/4 inches rather than 7 1/2 inches.

What does S4S mean?

S4S stands for surfaced four sides. The board has been planed smooth on both faces and both edges, and the edges are left square rather than rounded. Surfacing is the reason the actual size is smaller than the nominal size.

What is the difference between S4S and S1S2E?

S4S is surfaced on all four sides with square edges. S1S2E is surfaced on one face and two edges, so one face is smooth and the other is left textured, and both long edges are eased to a small radius. The net size is identical. S1S2E is reversible, which is why WindsorONE sells it as Eased All Edges and why it suits a board that has to work in more than one setting.

What does eased edge mean?

An eased edge is the long corner of a board broken to a small radius, roughly 1/32 to 1/16 inch, rather than left square. It holds paint better because a sharp corner tends to leave a thin paint film, it resists chipping in handling and transport, and it reads softer once installed. A square edge is crisper and is usually the choice for stain grade work or a modern detail.

What is S2S2E?

S2S2E is surfaced two sides and two edges, so both faces are planed smooth and both long edges are eased. It sits between S4S and S1S2E: two clean faces like S4S, but with the softened edges of S1S2E.

What is 5/4 lumber?

5/4, said five quarter, is a nominal 1 1/4 inch thickness. In our stock it surfaces to 1 inch in MDF and knotty alder, and 1 1/16 inch in poplar, WindsorONE and most other materials.

Do I order by nominal size or actual size?

Order by nominal size, because that is how boards are named, priced and stocked. Use the actual size for your cut list, your clearances and your material calculations.

Are WindsorONE boards the same size as regular boards?

Not at 5/4x or 2x. WindsorONE Protected measures 3/4 inch at 1x, which matches solid wood, but 1 1/16 inch at 5/4x and 1 7/16 inch at 2x. WindsorONE also comes in 16ft and 20ft lengths rather than the 8ft and 16ft used across the rest of our range.

Shop boards by size

1x, 5/4x and 2x boards in more than a dozen species, in 8ft and 16ft lengths, with 4 inch samples if you want to see a material first.

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Lumber Dimensions; Board Actual Size Guide

Lumber Dimensions and board actual size chart

The sizes people ask for most, answered

Nominal size versus actual size

Edge profiles and what the codes mean

Milled profiles

Full board size chart

2x board actual sizes

2x2 actual size

2x4 actual size

2x6 actual size

2x8 actual size

2x10 actual size

2x12 actual size

1x board actual sizes

1x2 actual size

1x3 actual size

1x4 actual size

1x5 actual size

1x6 actual size

1x8 actual size

1x10 actual size

1x12 actual size

1x16 actual size

5/4x board actual sizes

5/4x3 actual size

5/4x4 actual size

5/4x5 actual size

5/4x6 actual size

5/4x8 actual size

5/4x10 actual size

5/4x12 actual size

How each species measures

WindsorONE Protected net sizes

Common questions

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