The actual size of 1×6 lumber is around 3/4″ x 5 1/2″. Smaller than the size that is advertised. Because hardware stores measure 1×6 lumber when it was in its original shape, implying that when it was freshly sawed, had uneven surfaces and was thicker until it was planned to make the surfaces smoother.
Therefore, when measuring the dimension of 1×6 lumber by using a measurement tap, a difference is size. Nevertheless, despite being an incorrect measurement it is still referred to as 1-by-6 lumber in hardware stores due to the standard of measurement.
In spite of this, the length of a 1×6 board remains the same regardless of whether it is nominal or actual. For example, if the nominal length of 1×6 is 6 feet, the actual length will be 6 feet. Similarly, if the nominal length is 8 feet then the actual length would be 8 feet, and so a 12 feet length board will actually be 12 feet long, the same as the nominal length.
However, it’s better to do some quick measurements to find out the exact length.
1×6 lumber dimensions (Actual vs Nominal)
| 1×6 lumber | Nominal size in inches | Actual size in inches |
| Width | 1 Width | 3/4 |
| Height | 6 length | 5 1/2 |
| 1×6 Lumber | Nominal size in mm | Actual size in mm |
| Width | 25.4 | 19.05 |
| Height | 152.4 | 139.7 |
