Hole Saw Standard Sizes | Match The Cut To The Trade

Hole saw sizes are not universal; the right one depends on your trade and the material or pipe you are cutting.

Buying a hole saw without checking the application is a fast way to ruin material. There is no single “standard” chart that fits every job, even though most general-purpose kits land on a handful of common inch sizes. The reliable way to pick is to identify what you’re drilling for first, then match the hole saw to the trade-specific size. The table below shows what that looks like.

What Are The Common Hole Saw Sizes?

General-purpose hole saw kits sold for drilling in the US typically cover a span from 3/4 in to 6 in. Within that range, a few sizes show up again and again because they cover the most common residential and shop tasks.

• The frequently included sizes are 3/4 in, 7/8 in, 1-1/8 in, 1-1/4 in, 1-1/2 in, 2 in, 2-1/2 in, 3-1/2 in, 4-1/4 in, and 6 in.
• These sizes are not arbitrary; they track the clearance needs of standard pipes and fixture housings.
• The trade matters. A 1-1/8 in saw might be the right pick for a 3/4 in conduit, but that same saw could be the wrong choice for a woodworking plug.

Knowing these common sizes helps you recognize what’s in a kit, but it does not tell you which one to use. That decision comes from the application.

How To Pick The Right Size For Conduit And Pipe

Conduit and plumbing work use a clear rule: the hole is larger than the nominal pipe size to leave clearance for fittings and movement. Published trade charts map this out precisely.

For example, a 1/2 in conduit needs a 7/8 in hole saw, while a 3/4 in conduit takes a 1-1/8 in saw. The pattern scales up from there. This clearance prevents the pipe from binding against the hole and allows for the added width of connectors.

When you drill for a specific fixture like a downlight, the process changes. The sources consistently advise checking the fixture’s own cutout specification because there is no universal size for these. The manufacturer’s spec sheet, not a general chart, is the final authority on that job.

If you do this regularly, having a solid all-around option matters.

When the chart does not cover your part, or when you are working with a fixture, the cutout specification is the only number that matters. McMaster-Carr’s hole saw catalog organizes sizes by drill compatibility and material, which makes it a strong reference for verifying a match.

The key takeaway is to stop guessing. Check the pipe’s actual OD or the fixture’s spec sheet before you cut. A few minutes of verification beats a ruined door or a loose-fitting conduit.