Library › Hardware › Square keys, inch (ANSI B17.1): 3/32 to 1/2 in

0.125 in square key × 1.5 in, for shafts over 0.4375 up to 0.5625 in (keyway depth k/2 in shaft and hub)

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.

Set it up →

From the full sheet

Square keys, inch (ANSI B17.1): 3/32 to 1/2 in: every size, notes, mating features and sources. What key goes on a 1 inch shaft?

Other sizes

0.09375 in square key × 0.75 in, for shafts over 0.3125 up to 0.4375 in (keyway depth k/2 in shaft and hub)
0.09375 in square key × 1 in, for shafts over 0.3125 up to 0.4375 in (keyway depth k/2 in shaft and hub)
0.09375 in square key × 1.5 in, for shafts over 0.3125 up to 0.4375 in (keyway depth k/2 in shaft and hub)
0.09375 in square key × 2 in, for shafts over 0.3125 up to 0.4375 in (keyway depth k/2 in shaft and hub)
0.09375 in square key × 3 in, for shafts over 0.3125 up to 0.4375 in (keyway depth k/2 in shaft and hub)
0.125 in square key × 0.75 in, for shafts over 0.4375 up to 0.5625 in (keyway depth k/2 in shaft and hub)
0.125 in square key × 1 in, for shafts over 0.4375 up to 0.5625 in (keyway depth k/2 in shaft and hub)
0.125 in square key × 2 in, for shafts over 0.4375 up to 0.5625 in (keyway depth k/2 in shaft and hub)
0.125 in square key × 3 in, for shafts over 0.4375 up to 0.5625 in (keyway depth k/2 in shaft and hub)
0.1875 in square key × 0.75 in, for shafts over 0.5625 up to 0.875 in (keyway depth k/2 in shaft and hub)
0.1875 in square key × 1 in, for shafts over 0.5625 up to 0.875 in (keyway depth k/2 in shaft and hub)
0.1875 in square key × 1.5 in, for shafts over 0.5625 up to 0.875 in (keyway depth k/2 in shaft and hub)
0.1875 in square key × 2 in, for shafts over 0.5625 up to 0.875 in (keyway depth k/2 in shaft and hub)
0.1875 in square key × 3 in, for shafts over 0.5625 up to 0.875 in (keyway depth k/2 in shaft and hub)
0.25 in square key × 0.75 in, for shafts over 0.875 up to 1.25 in (keyway depth k/2 in shaft and hub)
0.25 in square key × 1 in, for shafts over 0.875 up to 1.25 in (keyway depth k/2 in shaft and hub)
0.25 in square key × 1.5 in, for shafts over 0.875 up to 1.25 in (keyway depth k/2 in shaft and hub)
0.25 in square key × 2 in, for shafts over 0.875 up to 1.25 in (keyway depth k/2 in shaft and hub)
0.25 in square key × 3 in, for shafts over 0.875 up to 1.25 in (keyway depth k/2 in shaft and hub)
0.3125 in square key × 0.75 in, for shafts over 1.25 up to 1.375 in (keyway depth k/2 in shaft and hub)
0.3125 in square key × 1 in, for shafts over 1.25 up to 1.375 in (keyway depth k/2 in shaft and hub)
0.3125 in square key × 1.5 in, for shafts over 1.25 up to 1.375 in (keyway depth k/2 in shaft and hub)
0.3125 in square key × 2 in, for shafts over 1.25 up to 1.375 in (keyway depth k/2 in shaft and hub)
0.3125 in square key × 3 in, for shafts over 1.25 up to 1.375 in (keyway depth k/2 in shaft and hub)
0.375 in square key × 0.75 in, for shafts over 1.375 up to 1.75 in (keyway depth k/2 in shaft and hub)
0.375 in square key × 1 in, for shafts over 1.375 up to 1.75 in (keyway depth k/2 in shaft and hub)
0.375 in square key × 1.5 in, for shafts over 1.375 up to 1.75 in (keyway depth k/2 in shaft and hub)
0.375 in square key × 2 in, for shafts over 1.375 up to 1.75 in (keyway depth k/2 in shaft and hub)
0.375 in square key × 3 in, for shafts over 1.375 up to 1.75 in (keyway depth k/2 in shaft and hub)
0.5 in square key × 0.75 in, for shafts over 1.75 up to 2.25 in (keyway depth k/2 in shaft and hub)
0.5 in square key × 1 in, for shafts over 1.75 up to 2.25 in (keyway depth k/2 in shaft and hub)
0.5 in square key × 1.5 in, for shafts over 1.75 up to 2.25 in (keyway depth k/2 in shaft and hub)
0.5 in square key × 2 in, for shafts over 1.75 up to 2.25 in (keyway depth k/2 in shaft and hub)
0.5 in square key × 3 in, for shafts over 1.75 up to 2.25 in (keyway depth k/2 in shaft and hub)