What Drill Bit

Hole saws for pipe & conduit

A pipe's nominal size isn't its real size, so the hole saw is never the nominal number. 2" PVC is 2.375" across. Conduit adds a second rule: into a box, the hole follows the knockout, not the pipe.

Start here Hole saw size finder Pick the pipe, its size and where it’s going, and get the hole saw: easy clearance, exact fit, or the knockout for a box. Find your hole saw Reference Hole saw size chartEvery pipe and conduit size on one sheet, with a printable PDF.

By pipe size

Know the pipe already? Jump straight to its saw.

2"PVC2-1/2" · exact 2-3/8" 1-1/2"PVC2-1/16" · exact 1-15/16" 3"PVC3-5/8" · exact 3-1/2" 4"PVC4-5/8" · exact 4-1/2" 1/2"conduit7/8" into a box 3/4"conduit1-1/8" into a box 1"conduit1-3/8" into a box 1/2"copper/PEX3/4" · exact 5/8" 3/4"copper/PEX1" · exact 7/8"

UK pipe

Metric copper, waste and soil pipe.

15 mmcopper19 mm · snug 16 mm 22 mmcopper27 mm · snug 24 mm 32 mmwaste40 mm · snug 37 mm 40 mmwaste48 mm · snug 44 mm 110 mmsoil114 mm · snug 111 mm

Reference

The sizes behind the answers.

PVC pipe sizeschartActual OD, 1/2"–4" Knockout sizeschartNEMA, 1/2"–4" UK pipe (mm)chartCopper, waste, soil Stud & joist holesguideIRC limits by lumber size

Elsewhere on What Drill Bit

Lumber sizessame nominal-vs-actual trapWhat drill bit for what materialWhat drill bit for metalDrill bit size chartholes under 1"Sizes & chartsthe hub

General sizing guidance from published pipe, conduit and hole saw dimensions. Before boring framing, check the hole limits in your local building code; for electrical work, follow your local electrical code and the fitting maker's instructions.