The Stanley Numbering System Explained

The Stanley numbering system has been the standard for classifying bench plane sizes since the 1870s. Understanding this system is essential for buying planes and communicating with other woodworkers.

The Basic Numbers

No. 1 - Thumb Plane (5½" long)

The smallest bench plane, rarely seen. Collectible but not practical for most work.

No. 2 - Smoothing Plane (7" long)

Small smoother, 1⅝" iron. Good for musical instruments and small work.

No. 3 - Smoothing Plane (8" long)

Compact smoother with 1¾" iron. Popular for small projects and finishing work.

No. 4 - Smoothing Plane (9" long)

The standard smoothing plane. 2" iron. This is the most common and versatile size. Perfect first plane.

No. 4½ - Smoothing Plane (10" long)

Wider than No. 4 with 2⅜" iron. More mass helps reduce chatter in figured wood.

No. 5 - Jack Plane (14" long)

The "jack of all trades." 2" iron. Can smooth, joint edges, and dimension stock. Extremely versatile.

No. 5½ - Jack Plane (15" long)

Longer and wider than No. 5 with 2⅜" iron. More stable for edge jointing.

No. 6 - Fore Plane (18" long)

Uncommon size between jack and jointer. 2⅜" iron. Less popular than No. 5 or No. 7.

No. 7 - Jointer Plane (22" long)

Long jointer for flattening boards and jointing long edges. 2⅜" iron. Essential for serious hand tool work.

No. 8 - Jointer Plane (24" long)

The longest standard bench plane. 2⅝" iron. Maximum flatness for large work.

The "sweet spot" trio for most woodworkers: No. 4 for smoothing, No. 5 for versatility, and No. 7 for jointing. These three handle 95% of bench plane tasks.

Specialty Designations

Block Planes

Other Planes

The "½" Designation

Planes with ½ added (4½, 5½) are wider versions with heavier castings. They cost more but offer better stability and reduced chatter.