convertimate Lumber sizes (nominal vs actual)

Actual inches to nominal inches

Type a value in in actual to get it in nominal instantly.

6nominal

That's 1.57× as wide as a 4×4 post, while a 2×10 joist’s depth is 1.68× wider.

What it means

How big is that board really?

Dry, surfaced softwood dimensions (PS 20). Convert each dimension separately: a 2×6 is 1½ by 5½ in. Hardwoods and rough-sawn lumber differ.

The math

How to convert in actual to nominal

Up to 6 in nominal, actual = nominal − ½ in; from 8 in, actual = nominal − ¾ in.

Example: 5 1/2 in actual = 6 nominal.

Every unit

That dimension in every unit

Tables

in actual to nominal conversion table

in actual to nominal conversion table
in actualnominal
3/4 in actual1 nominal
1 1/2 in actual2 nominal
2 1/2 in actual3 nominal
3 1/2 in actual4 nominal
4 1/2 in actual5 nominal
5 1/2 in actual6 nominal
7 1/4 in actual8 nominal
9 1/4 in actual10 nominal
11 1/4 in actual12 nominal
13 1/4 in actual14 nominal
15 1/4 in actual16 nominal
nominal to in actual conversion table
nominal to in actual conversion table
nominalin actual
1 nominal3/4 in actual
2 nominal1 1/2 in actual
3 nominal2 1/2 in actual
4 nominal3 1/2 in actual
5 nominal4 1/2 in actual
6 nominal5 1/2 in actual
8 nominal7 1/4 in actual
10 nominal9 1/4 in actual
12 nominal11 1/4 in actual
14 nominal13 1/4 in actual
16 nominal15 1/4 in actual

Quick answers

Quick answers

How many nominal is 1 in actual?
1 in actual is 1.5 nominal.
How many nominal is 10 in actual?
10 in actual is 11 nominal.
How many nominal is 5 1/2 in actual?
5 1/2 in actual is 6 nominal.

The units

About these units

Actual inches (in actual)

The real planed dimension in inches.

Nominal inches (nominal)

The name of the dimension: the 4 in 2×4.

Learn more about board size units

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