Materials
Plywood Thickness Chart and What Each Is For
A plywood thickness guide: 1/4, 1/2, 3/4 inch and more, their actual sizes, and what each thickness is used for in cabinets, shelves, and backs.
Research Lens
How can a personal builder use CutList to finish plywood thickness chart and what each is for with fewer mistakes?
The hobby workflow is strongest when the app is used as a planning checkpoint: define the project, enter accurate stock and parts, generate a visual layout, then use cost, waste, grain, kerf, PDF export, project history, and offline access to control the real cutting session.
Decision Metrics
Thickness Drives the Job
Plywood comes in a range of thicknesses, each suited to different parts. Choosing the right one balances strength, weight, and cost. Knowing what each thickness is for, and that the actual size is less than nominal, lets you spec parts correctly and avoid both flimsy and over-built results.
The Common Thicknesses
The workhorses are 1/4, 1/2, and 3/4 inch (actually about 7/32, 15/32, and 23/32). Quarter-inch suits backs and panels, half-inch suits drawers and light shelves, three-quarter-inch is the default for carcasses, shelves, and structure. Thinner (1/8) and thicker (1, 1-1/8) sheets exist for special uses.
What Each Is For
1/4 inch: cabinet backs, drawer bottoms, panels. 1/2 inch: drawer sides, light shelves, smaller boxes. 3/4 inch: cabinet sides, tops, bottoms, shelves, most structure. The thicker the part's job, the thicker the plywood, with 3/4 inch covering the majority of furniture and cabinet structure.
Mixing Thicknesses in One Project
A typical cabinet uses 3/4-inch for the carcass and shelves, 1/2-inch for drawer boxes, and 1/4-inch for the back, three thicknesses in one piece. Plan the cut list by thickness so you order the right sheets of each and cut them in their own groups.
Remember Actual vs Nominal
Because plywood is undersized, joinery must use the actual thickness. A dado for a 3/4-inch shelf is cut to about 23/32. Measure your specific sheets, as thickness can vary slightly by source. A thickness chart gets you close; your calipers confirm the real number for joinery.
Compare
Plywood thickness uses
| Nominal | Actual | Common use | Note |
|---|---|---|---|
| 1/4 in | ~7/32 | Backs, bottoms, panels | Light |
| 1/2 in | ~15/32 | Drawers, light shelves | Mid |
| 3/4 in | ~23/32 | Carcass, shelves, structure | Default |
| 1 in+ | ~ varies | Workbench tops, heavy | Special |
Field Checklist
- Match thickness to each part's job.
- Use 1/4 inch for backs and drawer bottoms.
- Use 1/2 inch for drawers and light shelves.
- Use 3/4 inch for carcasses and structure.
- Cut joinery to actual, not nominal, thickness.
FAQ
Common questions
What plywood thicknesses are there?
Common ones are 1/4, 1/2, and 3/4 inch (actually about 7/32, 15/32, 23/32), with thinner and thicker sheets for special uses.
What thickness plywood for cabinet backs?
1/4-inch plywood is standard for cabinet backs and drawer bottoms, set into a rabbet or groove to square and stiffen the box.
What thickness for cabinet sides and shelves?
3/4-inch plywood is the default for carcass sides, tops, bottoms, and shelves, giving the strength and screw holding structure needs.
Can I use different thicknesses in one cabinet?
Yes, and you usually should: 3/4-inch carcass, 1/2-inch drawers, 1/4-inch back, planned by thickness in the cut list.
Why measure thickness for joinery?
Plywood is undersized and varies slightly, so dados and grooves must match the actual thickness, around 23/32 for nominal 3/4-inch.
Sources