Best Drill Bits for Metal (2026)
By Nate Sawyer, Editor · Updated July 2026
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Drilling metal comes down to matching bit material to metal hardness, plus keeping the cutting edge cool. Titanium-coated HSS adds bite and life for aluminum and light-gauge steel, but the coating is only surface-deep, so once it wears the bit dulls fast. For stainless, hardened steel and cast iron you want solid cobalt (M35), which is hard all the way through and keeps cutting where coated HSS overheats. Tip geometry matters too - a split or quad-edge point starts without a center punch and resists walking. We compare two cobalt sets and a titanium set across heat resistance, tip design and value.
A metal-drilling workhorse: solid M35 cobalt (not just a coating) means the hardness goes all the way through, making it the pick for stainless, angle iron, and other hard metals that eat cheaper bits.
- Metal
- Stainless steel
- Hard metals
Pros
- Cobalt alloy runs cooler and holds an edge in stainless and hardened steel far better than plain HSS
- Pilot Point split tip starts on contact and stops walking, so you skip the center-punch step
- Bits can be resharpened multiple times, unlike coated bits that lose their edge once the coating wears
Cons
- More brittle than HSS - the tips can snap if you flex the bit or drill at an angle
- Set stops at 3/8 in, so you need a separate solution for larger holes
- Costs roughly double a titanium-coated set of the same piece count
A 14-piece HSS drill set (1/16-1/2 in.) with a titanium-nitride coating, a low-cost all-rounder for wood, plastic, and light-gauge steel. Split-point tips start without skating, and the 3-flat shank resists spinning in a keyless chuck. The TiN coating is only surface-deep, so bits dull fast in metal; they're not for stainless or hardened steel.
- Wood
- Plastic
- Light metal
Pros
- Cheap, versatile all-rounder that handles wood, plastic and thin metal in one household set
- Split-point tips give no-skate starts and clean holes without a pilot punch
- 3-flat shank on larger bits grips in a keyless chuck and resists spinning
Cons
- The TiN coating is only surface-deep - once it wears off, the bit dulls fast in metal
- Not suited to stainless or hardened steel where a true cobalt bit is needed
- Includes only one of each larger size, so a snapped 1/2 in leaves a gap
The Milwaukee 48-89-2370 is a 15-piece M35 cobalt drill bit set (1/16 to 3/8 in) engineered for stainless, hardened steel and cast iron. Because cobalt is hard all the way through, it keeps cutting where coated HSS overheats, and Milwaukee's Quad Edge tip plus a variable RED HELIX flute start faster and clear chips to fight the heat that kills metal bits. It costs more than titanium sets but earns it on tough metal, though round shanks can slip under heavy torque.
- Metal
- Stainless steel
- Hard metals
Pros
- Solid cobalt runs cool and lasts up to 15x longer than black-oxide bits in hard metal
- Quad Edge tip has four cutting edges for faster starts and less walking
- Variable 35-to-15-degree RED HELIX flute ejects chips quickly to reduce heat
Cons
- Costs more than titanium-coated HSS sets
- Round shanks can slip in keyless chucks under high torque
- Overkill for wood and plastic where cheaper bits do the job
Still deciding? Compare them
Frequently Asked Questions
- What kind of drill bit is best for stainless steel?
- A solid cobalt (M35) bit like the DeWalt DWA1240 or Milwaukee RED HELIX. Cobalt is hard all the way through and runs cooler, so it keeps cutting stainless where a titanium-coated HSS bit quickly overheats and dulls.
- Are titanium-coated bits good for metal?
- For light-gauge steel, aluminum and occasional use, yes - the coating adds bite and life over bare HSS. But the coating is surface-deep, so for hard or stainless steel a through-hardened cobalt bit lasts far longer.
- How do I keep drill bits from overheating in metal?
- Run at a slower speed with steady pressure, use cutting oil, and back the bit out to clear chips. Heat is what kills metal bits; low RPM plus lubrication preserves the cutting edge.