2x10 True Size and Actual Dimensions

Dry or green, a 2x10 is exactly 2 inches wider than a 2x8: 9-1/4 against 7-1/4 dry, 9-1/2 against 7-1/2 green. Both lose 3/4 inch to drying and planing; the narrower board is on the 2x8 actual size page.

Green redwood and cedar 2x10s are 9-3/8 inches wide (238.1 mm), 1/8 inch under the green figure for other woods.

In section it keeps 69% of its nominal area, 13.88 of 20 square inches, the most of the four 2x sizes covered here.

None of the sellers in our data publishes a list of 2x10 lengths. PS 20-25 leaves lengths to the grading rules, in steps of 1 or 2 feet, and the Wood Handbook notes that even 2 ft steps are the usual habit for construction lumber.

A trimmed piece is never shorter than its stated length and may run up to 3 inches over. Past 20 ft the allowance for nominal 2 inch stock grows to 12 inches, worth knowing before you cut a long 2x10 to fit.

Wolf's Perspective guide asks for joists of 2 by 8 inches or larger, and a 2x10 clears that with 2 inches of depth to spare. Our Deck Calculator draws the frame; the span a 2x10 may cover is set by your local code, which this page does not quote.

Each foot of a 2x10 tallies 1.67 board feet, so a 12 ft piece comes to 20 board feet. Longer lists go through the board foot calculator.

Thick pours, over 7-1/4 and up to 9-1/4 inches, are boarded with 2x10s. The concrete slab calculator picks the board that way, and the nominal vs actual lumber sizes table lists the rest.