How to Drill a Hole in Metal: Bits, Speed and Tips

Use a sharp twist bit made for metal, ideally high speed steel or cobalt, and run it slowly with steady pressure and cutting oil. Mark the spot with a center punch, start with a small pilot hole, then step up to the final size. Clamp the work, wear eye protection, and let the bit cut instead of forcing it.

Which drill bit is designed for drilling through metal

A twist bit made of high speed steel (HSS) is the standard choice for metal. Many are coated with black oxide or titanium nitride, which helps them resist heat and wear. These work well on mild steel, aluminum, brass and copper.

For harder jobs such as stainless steel, pick a cobalt bit. Cobalt bits hold their edge at higher temperatures, which matters because heat is what dulls a bit in metal. If you drill tough metals often, see our comparison of the best cobalt drill bits.

Do not use wood bits, spade bits or masonry bits on metal. Masonry bits have a carbide tip built for brick and concrete, not for steel. Our best masonry drill bits page covers where those belong.

Bit types at a glance

This table summarizes common options and what each is best at. It is general guidance, not a rating of specific products.

Bit type	Best for	Notes
HSS twist bit	Aluminum, brass, mild steel	Good everyday choice for thin to medium stock
Black oxide or titanium coated HSS	Mild steel, repeated use	Coating resists heat and wear better than plain HSS
Cobalt twist bit	Stainless steel, hardened or tough metal	Holds up to heat, but is more brittle if you wobble or bend it
Step bit	Thin sheet metal, enlarging holes	Cuts clean round holes and often needs no pilot
Center punch (not a bit)	Marking the start point	Stops the bit from wandering

Choose the right speed

Slow is the rule for metal. Spinning too fast builds heat at the cutting edge, and that dulls the bit and can harden stainless steel so it becomes harder to cut. As a general guide, small bits can spin faster than large ones, and harder metals need slower speeds than soft ones.

Use your drill's low speed range for most metal work. Drills with two speed settings make this easy. The DEKOPRO 20V drill, for example, lists a low range of 0 to 350 rpm and a high range up to 1350 rpm. The DEWALT DCD806B lists 0 to 650 rpm on low and up to 2000 rpm on high. Use the low range for steel and keep the high range for small holes in soft metal or for driving screws.

Pressure matters as much as speed. Firm, steady pressure makes the bit cut a curl of metal. If you only see dust or the bit squeals, you are probably pressing too lightly or spinning too fast.

Step-by-step: drilling a clean hole

Follow this sequence for steel, aluminum or similar stock.

Clamp the metal firmly to a bench or vise. Never hold small pieces by hand, because the bit can grab and spin the work.
Mark the hole location, then tap a center punch to make a small dimple. This keeps the bit from skating.
Put on safety glasses and gloves that will not catch in the chuck. Tie back long hair and remove loose sleeves.
Start with a small pilot bit, about 1/8 in for most holes, at low speed.
Add a few drops of cutting oil to the spot. Reapply as you go, especially on steel and stainless.
Drill with steady pressure. Back the bit out now and then to clear chips and let it cool.
Switch to the final bit size. For large holes, step up in two or three stages instead of jumping straight to the biggest bit.
Ease off the pressure as the bit breaks through, since that is when it is most likely to grab.
Remove the sharp burr around the hole with a larger bit twisted by hand or a deburring tool.

What drill works best for metal

Most cordless drills can handle small holes in thin metal, but check the specs. Low-speed torque and a solid chuck grip matter more than top speed. A 1/2 in chuck holds larger bits securely, which helps when you step up to bigger holes. Our best drill page lists chuck size, speed and weight for each model so you can compare.

Be realistic about small drills. The AVID POWER CD316-20 is a light 2.19 lb drill with a 3/8 in keyless chuck and a top speed of 550 rpm. Its listing says it is rated for steel plate up to 3/8 in, so it suits light household work rather than repeated heavy drilling.

If you use a hammer drill such as the DEWALT DCD806B, turn off hammer mode when drilling metal. Hammering damages the bit and gives a rough hole.

If you need to enlarge, shape or clean up a hole afterward, a die grinder with the right burr can help. See the best die grinder bits for metal for options.

Safety notes

Metal drilling throws sharp chips and creates hot bits and hot workpieces. Take these precautions every time.

Wear safety glasses or goggles to protect your eyes from flying chips.
Use hearing protection if the bit screams or you are drilling a lot of holes.
Let the bit and metal cool before touching them. Fresh holes and chips can burn.
Keep cutting oil off the floor and away from heat sources, and wipe up spills.
Remove the battery before changing bits or when the drill is not in use.
Do not wear gloves with loose cuffs near a spinning chuck. Use snug gloves or none at all.

Frequently asked questions

Can I drill metal with a regular wood bit?

It is not a good idea. Wood bits have points and cutting edges designed for fibers, so they dull or burn quickly in metal and make rough holes.

Why does my bit stop cutting or turn blue?

Blue or dark discoloration means the bit got too hot. It is usually caused by too much speed, too little pressure or no lubricant. Slow down, add oil and use a sharp bit.

Do I need a pilot hole?

For anything larger than a small hole, yes. A pilot hole guides the larger bit, reduces the force needed and helps keep the hole round and in the right place.

What is the best lubricant for drilling metal?

Use a cutting oil or tapping fluid made for metal. In a pinch, light machine oil works on steel. Aluminum often drills well with a little oil or wax to stop chips sticking.