Plywood sheet sizes and actual thickness

Published October 5, 2026. Every number below links to the standard, manufacturer document or dealer listing it comes from (sources).

Short answer: in the U.S. and Canada a full sheet of plywood is 4 × 8 ft (48 × 96 in., 1219 × 2438 mm). Birch plywood made in Europe comes in metric sizes such as 1220 × 2440, 1250 × 2500 and 1525 × 3050 mm, and Baltic birch is commonly stocked in 5 × 5 ft sheets. Thickness names are nominal: "3/4 in." hardwood plywood may be anywhere from 0.703 to 0.750 in. thick and still be within tolerance, and 18 mm birch is 0.709 in. at nominal size, with one mill allowing as little as 0.673 in. Measure before you cut dadoes or work out parts that fit between two sides.

Standard sheet sizes

Millimetre and area figures are conversions of the inch sizes, rounded.

Sheets are not always exactly 48 × 96 in.

• Structural plywood can be a little small. PS 1-22 allows a panel to be up to 1/16 in. (1.6 mm) under the manufacturer's stated length and width, and up to 1/8 in. (3.2 mm) under when it is marked "sized for spacing". APA explains that sized-for-spacing sheathing is made slightly smaller than 48 × 96 in. so it can be installed with gaps (TT-055).
• Edges may not be square. The same standard requires panels to be square within 1/64 in. per foot of the long edge, measured along the diagonals (1/8 in. on an 8 ft sheet), and each edge to be within 1/16 in. of a straight line between its corners. If your project needs a perfectly square reference edge, set an edge trim in the optimizer.
• MDF, melamine and some hardwood plywood run large. 49 × 97 in. is a common MDF and melamine size, and Columbia Forest Products quotes the weight of its Classic Core hardwood plywood for a 48 1/2 × 96 1/2 in. panel (Classic Core).

Metric sizes and grain direction

European birch plywood mills list sizes in millimetres. UPM's WISA birch range includes 1220 × 2440, 1250 × 2500, 1500 × 2500 or 3000, 1525 × 3050 or 3660 and 2000 × 2000, 2500 or 3000 mm. Riga Wood's Riga Ply datasheet lists panels 1220/1250, 1500/1525, 1830/1850 and 2150 mm by lengths up to 4000 mm, with face veneers in either long grain or cross grain.

Watch the order of the numbers. UPM states that the first dimension in a WISA size runs parallel to the face grain, so a 1250 × 2500 mm WISA panel has its face grain running the 1250 mm way, parallel to the short edges, while a 2500 × 1250 mm panel has it running the long way. Check how your supplier writes sizes. In the optimizer, enter the dimension that runs along the grain as the sheet's length.

Nominal vs. actual thickness

Plywood is sold by a nominal thickness, and the sheet is often a little thinner. How much depends on which standard the panel is made to.

Structural plywood (PS 1)

Sheathing, subfloor and sanded construction grades made under PS 1-22 are labeled with a Performance Category, such as "23/32 CAT", plus a decimal thickness. APA notes that panels have carried both labels since 2008, and that the Performance Category is what building codes use as the "nominal" thickness (APA, Plywood; TT-054). The standard sets these thickness ranges:

Source: PS 1-22, Table 10. The ranges come from a tolerance of ±1/64 in. (0.4 mm) for sanded panels and ±1/32 in. (0.8 mm) for unsanded panels around each category. Overlaid grades follow the unsanded column.

So a "3/4 in." sheathing panel stamped 23/32 CAT may be as thin as 0.688 in., and a sanded 23/32 panel is 0.703 to 0.734 in.

Hardwood (cabinet) plywood

Veneered hardwood plywood such as maple, birch and oak cabinet grades is made to a different standard, ANSI/HPVA HP-1. That standard is not free to read, so we rely on what a manufacturer publishes about it: Columbia Forest Products describes the HPVA thickness tolerance as +0 / −3/64 in., which for a 3/4 in. panel means 0.703 to 0.750 in. In Columbia's own tests, 3/4 in. Classic Core measured 0.726 in. and a softwood veneer core panel 0.721 in., and for buyers who need something closer to a full 3/4 in. Columbia offers a 19.5 mm (0.767 in.) Classic Core panel (Classic Core). Columbia also notes that veneer core typically varies more in thickness than engineered cores such as MDF (FAQ).

Metric birch plywood

Source: Riga Wood, Riga Ply datasheet (sanded birch plywood, at 9 ± 3% moisture content). Inch values are conversions. Other mills, including UPM for WISA birch, publish their own tolerance tables.

An 18 mm birch sheet, often used in place of 3/4 in. plywood, is 0.673 to 0.713 in. thick by this spec, roughly 1/32 to 5/64 in. thinner than a true 3/4 in. A dado cut with a 3/4 in. bit will be loose; cut a test slot or use an undersized plywood bit.

Baltic birch

"Baltic birch" is the common North American name for all-birch plywood with many thin, solid inner plies and few voids. It is sold in millimetre thicknesses:

• Sizes. Dealers commonly stock 5 × 5 ft (60 × 60 in.) sheets, and some also list 5 × 10 ft (60 × 120 in.) Baltic birch and 4 × 8 ft birch panels (Commonwealth Plywood, Capitol City Lumber).
• Thicknesses. Dealers commonly list 3, 6, 9, 12, 15, 18 and 24 or 25 mm. European mills list a wider range: Riga Ply from 4 to 50 mm, and WISA birch from 6.5 to 50 mm as standard.
• Plies. Riga Ply is built from 1.45 mm birch veneers: 5 plies at 6.5 mm, 9 at 12 mm, 13 at 18 mm and 17 at 24 mm (full list in the table above). Dealer listings use similar counts, for example 13 plies for an 18 mm birch panel at Commonwealth Plywood.
• Planning on a 5 × 5 sheet. The extra width changes what fits. Two 24 in. deep cabinet sides side by side need 48 1/8 in. with a 1/8 in. kerf, which is more than a 48 in. sheet offers. On a 60 in. sheet they fit with an 11 3/4 in. strip to spare.

MDF and melamine

• No grain. Plain MDF, particleboard and solid-color melamine have no grain, so set the sheet's grain to none in the optimizer and let every part rotate. Keep grain locked on woodgrain-print melamine and veneered MDF, where the pattern shows.
• Oversize sheets. Commonwealth Plywood lists standard MDF as 3/4 × 49 × 97 in., and Tafisa melamine panels in 5/8 and 3/4 in. thicknesses at 49 × 97 and 61 × 109 in. Enter the size you actually buy.
• Chipping. Melamine faces chip easily where the blade exits. A sharp blade with a high tooth count, a zero-clearance insert or a track saw's splinter guard, and good support under the cut all help.

What to enter in the optimizer

1. Measure the length and width of the sheets you actually have, and enter those numbers.
2. Enter the dimension that runs along the face grain as the sheet's length, or set grain to none.
3. If you will clean up factory edges, enter that amount as edge trim.
4. Use the measured thickness when you work out part sizes, for example parts that fit between two sides.

Then lay out your parts with the cut list optimizer, or count sheets with the plywood sheet calculator.

Sources

1. NIST, Voluntary Product Standard PS 1-22, Structural Plywood: size, squareness and thickness requirements (sections 5.10.1 to 5.10.3, Table 10).
2. APA – The Engineered Wood Association, Plywood: Performance Category and decimal thickness labeling.
3. APA, Technical Topic TT-054, Panel Thickness Tolerances and Labeling.
4. APA, Technical Topic TT-055, Sized for Spacing.
5. Columbia Forest Products, Classic Core: HPVA thickness tolerance, measured thickness, 19.5 mm panel, panel size for weights.
6. Columbia Forest Products, Frequently asked questions: thickness variation by core type.
7. Columbia Forest Products, CFP60"s: 60 in. wide hardwood plywood.
8. UPM WISA, Sizes, thicknesses and weights: birch plywood sizes, grain direction convention, standard thicknesses.
9. Riga Wood (Latvijas Finieris), Riga Ply datasheet (10/2025): sizes, standard thicknesses, veneer thickness, plies and thickness limits.
10. Commonwealth Plywood (dealer), birch plywood panels, 60 × 120 in. Baltic birch, 18 mm 13-ply birch, MDF Board, Standard and Tafisa melamine panels (range, 61 × 109 in. example): listed sizes, thicknesses and ply counts.
11. Capitol City Lumber (dealer), Baltic Birch Plywood: 60 × 60 in. sheets, 3 to 25 mm.