Plywood Thickness Chart
Plywood is sold by nominal size, but the actual panel is usually 1/32 inch thinner. This chart lists the real thickness of each common size in fractions, decimal inches, and millimeters, so you can size dadoes, fasteners, and stacked layers correctly.
Nominal vs. actual plywood thickness
| Nominal | Actual | Actual (decimal in) | Actual (mm) | Metric panel |
|---|---|---|---|---|
| 1/4" | 7/32" | 0.2188 | 5.6 | — |
| 3/8" | 11/32" | 0.3438 | 8.7 | 8.7 mm |
| 1/2" | 15/32" | 0.4688 | 11.9 | 12 mm |
| 5/8" | 19/32" | 0.5938 | 15.1 | 15 mm |
| 3/4" | 23/32" | 0.7188 | 18.3 | 18 mm |
| 1-1/8" | 1-1/8" | 1.1250 | 28.6 | — |
Sanded hardwood and cabinet plywood can differ from these structural-panel values; measure before cutting joinery.
How many sheets of plywood?
5 sheets of 4 × 8
120 sq ft + 10% = 132.0 sq ft ÷ 32 sq ft per sheet, rounded up.
Plywood Thickness Chart FAQ
How thick is 3/4 plywood really?
Most 3/4 in structural plywood is 23/32 in (0.719 in, about 18.3 mm) thick, 1/32 in less than the name. Panels are labeled with this thickness or the matching performance category.
Why is plywood thinner than its nominal size?
Plywood is sold by a nominal size, but panels are made to a slightly smaller labeled thickness, typically 1/32 in under for 1/4 through 3/4 in panels. Always measure if a dado or joint needs a tight fit.
What size is a sheet of plywood?
The standard sheet is 4 × 8 ft (1220 × 2440 mm). Some mills also make metric 1200 × 2400 mm panels and longer 4 × 10 or 4 × 12 ft sheets.
Is 15/32 the same as 1/2 inch plywood?
In stores, yes: a sheet sold as 1/2 in is usually 15/32 in thick. Full 1/2 in panels also exist, so check the label if the exact thickness matters.
Sources
Nominal-to-actual values agree between Inch Calculator's plywood thickness chart and Hansen Pole Buildings' nominal vs. actual list, and match the thickness designations and metric equivalents in APA's “Understanding the APA Trademark” (2015). Sheet sizes from the same APA guide. Millimeters are inches × 25.4.