Plywood Thickness Chart

Compare common plywood thickness labels with the actual thickness ranges permitted by PS 1-22 for sanded and unsanded structural plywood, in inches and millimeters.

PS 1-22 Structural Plywood Thickness Chart

DOC PS 1-22 Table 10. Default: sanded; switch the finish condition for the alternate published range.

Looking for “actual plywood thickness”? PS 1-22 does not use one universal nominal-to-actual conversion: each Performance Category has an allowed thickness range, and 23/32 and 3/4 are separate categories.

23/32 Performance Category · sanded 0.703–0.734 in 17.86–18.65 mm Recommended thickness label: .703 in Table 10 range · Appendix D2 recommended label (nonmandatory) · dimensional measurements are based on 9% moisture content.

PS 1-22 Table 10 permitted thickness ranges for sanded structural plywood grades. Inch values are shown with the standard’s corresponding millimeter values.
Performance Category	Minimum Thickness	Maximum Thickness
1/4	0.234 in 5.95 mm	0.266 in 6.75 mm
5/16	0.297 in 7.54 mm	0.328 in 8.33 mm
11/32	0.328 in 8.33 mm	0.359 in 9.13 mm
3/8	0.359 in 9.13 mm	0.391 in 9.92 mm
7/16	0.422 in 10.72 mm	0.453 in 11.51 mm
15/32	0.453 in 11.51 mm	0.484 in 12.30 mm
1/2	0.484 in 12.30 mm	0.516 in 13.10 mm
9/16	0.547 in 13.89 mm	0.578 in 14.68 mm
19/32	0.578 in 14.68 mm	0.609 in 15.48 mm
5/8	0.609 in 15.48 mm	0.641 in 16.27 mm
11/16	0.672 in 17.07 mm	0.703 in 17.86 mm
23/32	0.703 in 17.86 mm	0.734 in 18.65 mm
3/4	0.734 in 18.65 mm	0.766 in 19.45 mm
13/16	0.788 in 20.02 mm	0.837 in 21.26 mm
7/8	0.849 in 21.56 mm	0.901 in 22.89 mm
1	0.970 in 24.64 mm	1.030 in 26.16 mm
1-1/8	1.091 in 27.72 mm	1.159 in 29.43 mm
1-1/4	1.213 in 30.80 mm	1.288 in 32.70 mm

Performance Category is a designation, not an exact measured thickness. These are permitted ranges for PS 1-22 structural plywood, not a universal nominal-to-actual conversion for every plywood product. PS 1-22 permits other Performance Categories beyond the published Table 10 set.

Print scope: PS 1-22 structural plywood Table 10 ranges, with the selected finish condition and supporting source notes.

23/32 vs. 3/4 Plywood Thickness

PS 1-22 treats 23/32 and 3/4 as separate Performance Categories. For sanded panels, their permitted ranges meet at 0.734 in. For unsanded, touch-sanded, and overlaid panels, the wider permitted ranges overlap from 0.719 to 0.750 in.

Source: DOC PS 1-22 Table 10. The ranges are limits for the specified Performance Category and finish condition, not a statement that every panel measures at the midpoint.

Common adjacent Performance Categories, using the PS 1-22 sanded-panel ranges.
Comparison	First range	Second range
15/32 vs 1/2	0.453–0.484 in	0.484–0.516 in
19/32 vs 5/8	0.578–0.609 in	0.609–0.641 in
23/32 vs 3/4	0.703–0.734 in	0.734–0.766 in

These pairs are separate PS 1-22 Performance Categories even where their permitted ranges share a boundary or overlap under another finish condition.

What Does Plywood Thickness Actually Mean?

For structural plywood covered by PS 1-22, a Performance Category is a designation tied to a permitted thickness range. It is not a promise that every panel in that category measures exactly the fraction printed in the category name.

There is no single universal nominal-to-actual plywood conversion. A retail nickname can be useful in conversation, but for PS 1-22 structural plywood the Performance Category and finish condition control the published thickness range. In particular, 23/32 and 3/4 are separate Performance Categories.

Use the panel mark

For specification or fit-up work, identify the applicable standard and Performance Category, then use the permitted or declared thickness information. Measure the actual panel when a joint, groove, dado, or hardware fit depends on the real thickness.

Sanded vs. Unsanded Plywood Thickness

PS 1-22 uses different tolerance rules for the two finish groups in Table 10. For Performance Categories of 3/4 and less, sanded panels use a tighter ±0.4 mm (1/64 in) basis; unsanded, touch-sanded, and overlaid panels use ±0.8 mm (1/32 in) through 13/16. Above those thresholds, the standard uses percentage tolerances unless a closer tolerance is established through qualification testing.

That difference is why the selector changes both the minimum and maximum value rather than treating finish as a cosmetic label.

Hardwood Plywood Uses a Different Thickness System

ANSI/HPVA HP-1-2024 covers hardwood and decorative plywood and uses a separate Thickness Class concept. The class designation is not an actual measured dimension. The standard requires actual thickness information and allows the stated class to be reduced by up to 3/64 in (0.047 in / 1.2 mm) for classes at or above 1/4, and by up to 1/32 in (0.031 in / 0.8 mm) for classes below 1/4.

Do not apply the PS 1-22 structural-plywood ranges above to decorative hardwood plywood unless the product is actually specified to PS 1-22.

How Should Plywood Thickness Be Measured?

A shop caliper check is useful for fitting parts, but it is not the complete PS 1-22 conformity procedure. Section 5.10.2 specifies a micrometer with 19.1 mm (3/4 in) anvils, 34–69 kPa (5–10 psi) applied pressure, measurements near the mid-length of all four panel edges, and the average of those four measurements. Dimensional measurements in Section 5.10 are based on 9% moisture content.

For woodworking fit, measure the actual sheet you will use. For standards conformance or procurement, follow the governing standard’s specified method.

Plywood Thickness Measurement

The drawing explains the measurement direction only. The formal PS 1-22 conformity method also controls anvil size, pressure, measurement locations, and averaging.

Sources and Reference Scope

The structural-plywood dataset above was transcribed from every row of DOC PS 1-22 Table 10 and checked against the current NIST-hosted standard. No interpolation or extrapolation is used. Metric and inch range values are displayed as published; PS 1-22 states that SI values are the standard values and parenthetical U.S. customary values are informational. The selected-result recommended thickness label comes from nonmandatory Appendix D1 or D2; when Appendix D2 does not list a sanded label for 19/32, the page reports that instead of inventing one.

U.S. Department of Commerce / NIST — Voluntary Product Standard PS 1-22, Structural PlywoodEffective October 2, 2023. Primary locators: §5.10, §5.10.2 and Table 10; Appendix D1/D2 supply nonmandatory recommended thickness labels.
NIST Voluntary Product Standards ProgramLists DOC PS 1-22 as the current Structural Plywood standard and PS 1-19 as superseded.
ANSI/HPVA HP-1-2024 — American National Standard for Hardwood and Decorative PlywoodUsed only for the separate hardwood/decorative Thickness Class distinction in §3.13.

Structural scope: 18 published PS 1-22 Table 10 Performance Categories; both finish groups
Reference condition: PS 1-22 dimensional measurements based on 9% moisture content
Precision: Source-published values: inches to 0.001 in; millimeters to 0.01 mm
Source checked: September 28, 2026
Not covered: OSB, MDF, particleboard, Baltic birch, imported metric products, specialty panels, or manufacturer-specific tolerances

Common Plywood Thickness Questions

How thick is 3/4 plywood actually?

PS 1-22 does not define one exact “actual thickness” for 3/4 plywood. A sanded 3/4 Performance Category panel may measure 0.734–0.766 in (18.65–19.45 mm), while unsanded, touch-sanded, and overlaid panels may measure 0.719–0.781 in (18.26–19.84 mm). Other plywood standards and manufacturer products can use different rules.

Is 23/32 plywood the same as 3/4 plywood?

No universal equivalence should be assumed. PS 1-22 lists them as separate Performance Categories. For sanded panels, 23/32 permits 0.703–0.734 in and 3/4 permits 0.734–0.766 in; for unsanded, touch-sanded, and overlaid panels, the ranges overlap from 0.719 to 0.750 in.

Is 18 mm plywood the same as 3/4 inch plywood?

No. 18 mm is approximately 0.7087 in, while 3/4 in is exactly 19.05 mm. Products labeled around those sizes may be used for similar work, but dimensional equivalence should not be assumed.

What does 23/32 mean on plywood?

On PS 1-22 structural plywood, 23/32 is a Performance Category. It identifies a permitted thickness range under the applicable finish condition; it does not mean every conforming panel measures exactly 23/32 in.

Why does plywood thickness vary?

For PS 1-22 structural plywood, thickness is controlled as a permitted range rather than one exact measurement. The allowed range depends on the Performance Category and whether the panel is sanded or in the unsanded/touch-sanded/overlaid group; categories above specified thresholds also use percentage tolerances unless closer tolerances are qualified.

For material context, see Timber Materials. For floor framing, use the separate Floor Joist Span Chart; joist span and panel thickness are different design decisions. Return to the Engineering Charts & Tables hub for other references.