10 Best Metal Drill Bits Cutting Metal in 2026

An 8% cobalt M42 alloy gives these bits a serious edge for tough metals like stainless steel and cast iron. That composition provides the high heat resistance you need when the shavings start turning blue, and the thick web-helix design keeps them from walking or chattering on curved surfaces. This set hits the sweet spot for the serious DIYer or metal fabricator who needs a reliable, versatile range from 1/16 inch up to a half-inch. You get a durable foundation that covers most common metalworking tasks without having to buy bits individually.

Research indicates that in extreme, continuous drilling tests on thick stainless steel, a dedicated bit like the Adiseal Ultimate significantly outlasted the Bosch. For a professional drilling hundreds of identical holes, that lifespan difference is a critical factor. However, for most workshop applications involving a mix of materials and hole sizes, the Bosch CO14B’s balanced performance and comprehensive size assortment make it a dependable, go-to kit. It’s a more versatile choice than a niche, top-performing bit like the Adiseal, offering great all-around utility for the money.

A 135-degree split point tip is the star here, biting in immediately to prevent the bit from skating across hard metal surfaces. This DeWalt set is built for the DIYer or tradesperson who needs reliable performance across a variety of materials without a premium investment. The black oxide coating fights rust, and the parabolic flute helps clear chips when you’re drilling deeper holes, so you spend less time backing out. It’s a solid, no-fuss toolkit for drilling through mild steel, wood, and plastics on a regular basis.

High-speed steel construction makes these bits ideal for general-purpose drilling in metal, wood, PVC, and fiberglass, offering strong performance for most common materials. This material is a practical choice for a home shop tackling occasional metal projects, delivering good value. When drilling hardened steel or stainless steel all day, cobalt bits are typically chosen for their edge retention; the research test on stainless steel used dedicated cobalt bits from other brands.

For general steel drilling, the more affordable M35 cobalt in this 29-piece set balances price and performance, making it a frequently reached-for kit for tradesmen. Its Red Helix geometry works well with cordless drills, according to expert feedback. The set provides the core fractional sizes needed for daily metal work in construction and fabrication.

The trade-off is in specialization. This is a fractional set, so it doesn’t include the numbered or lettered bits required for precise tapping and machining operations. For that level of shop work, you’d need to look at a dedicated machine shop index from a brand like Drill America. Compared to a more compact set like the Bosch CO21, the Milwaukee’s larger case holds more bits but takes up more space in your kit.

Cobalt construction makes these bits stand out for tough metalwork, as they are designed to drill faster and last longer in hardened materials like steel. Their self-centering tip geometry helps the bit start easier and reduces walking, while the three-flat shank prevents spinning in the chuck. This set suits a tradesperson or serious DIYer who needs to create or enlarge holes in acrylic, steel, brass, and other hardened metals.

The trade-off is in the sizing. This is a fractional inch set, pure and simple. If your projects require precise number or letter drill sizes for tapping threads, you’ll need to look elsewhere, like a dedicated machine shop set. For general construction and fabrication on hardened materials, however, the range from 1/16″ to 1/2″ in 64th increments is comprehensive. Compared to a more general-purpose set like the DeWalt DWA1181, these cobalt bits are in a different league for durability on hard metals, but they’re specialized for that single, demanding task.

Impact-rated for use in 1/4-inch hex drivers, these bits let you drill directly with an impact driver, a tool many already carry for screws. Their titanium nitride coating lasts 2.5 times longer than non-coated bits. The 135-degree split point geometry promotes faster starts with less walking, making the set suitable for drilling ferrous metal, wood, plastic, non-ferrous metal, cast iron, and stainless steel. This is ideal for tradespeople or serious DIYers who want to maximize a single tool during assembly or repair.

Containing 14 pieces, this is a strategic set for common tasks rather than a comprehensive workshop collection. For high-volume metal drilling with a standard drill or press, a larger set like the 14-piece Bosch CO14B provides more size options. The Makita set excels in driver-centric environments, but a more extensive cobalt set may serve better if your primary tool is a standard drill and you require a wider variety of hole sizes in metal.

The 5% cobalt alloy in these bits is the key feature for anyone regularly drilling hard metals. That composition directly fights the heat and abrasion that dulls standard high-speed steel, letting you push harder for longer in stainless steel or cast iron without stopping to cool the bit. This 29-piece set covers a full range from 1/16 to 1/2 inch in fine increments, so you have the exact size for tap drills or clearance holes.

The storage case is large, measuring 12.3 inches wide, so it requires significant drawer or shelf space in a workshop. Compared to more compact sets like the Bosch CO14B, this Irwin set trades portability for its durable cobalt alloy construction suited for demanding metal drilling.

The 3-flats shank is the star here, gripping the chuck with authority so the bit doesn’t slip and scar your workpiece. That’s a huge benefit when drilling overhead or at awkward angles. Combined with the 135° split point that bites in without wandering, this DeWalt set is a solid, reliable choice for the DIYer or pro tackling a mix of steel, wood, and plastic. It’s built for the shop with a durable tapered web and clear size markings, making it a workhorse you can grab without second-guessing.

High-speed steel construction makes these bits suitable for drilling plastic, wood, and metal, covering common materials for home improvement and general tasks. The self-centering tip design helps reduce walking on curved surfaces, allowing for more precise hole starting. A black and gold coating provides protection against rust and wear, helping to maintain the set over time.

The 5% M35 cobalt alloy is the key here, giving these bits the heat resistance and hardness needed to chew through stainless steel and cast iron without immediately dulling. This set is built for the metalworker who regularly encounters hardened materials and needs a bit that won’t give up on the first hole. The 135-degree split point design bites into slick metal surfaces without walking, so you spend less time center-punching and more time drilling.

Covering sizes from 1/16-inch to 1/4-inch, this set provides a focused range for detailed metal fabrication and repair tasks. Its thirteen cobalt bits target common small-hole applications in hard materials, so you are not paying for or storing sizes you might rarely need. This makes the kit a straightforward and capable choice for a dedicated bench workspace where those specific diameters are used regularly.

A 99-piece set with 14 SAE sizes gives you a drill bit for nearly any common task around the house, from metal brackets to wood shelves. The titanium nitride coating on the high-speed steel adds a legitimate layer of durability, fighting off the heat and abrasion that dulls cheaper bits. This is the set you grab when you need to tackle a mixed bag of projects and don’t want to hunt for the right size, it’s all there in the organized tray. For the DIYer building up a workshop from scratch or the homeowner who wants one comprehensive kit, this variety eliminates guesswork and frequent store runs.

This set includes 99 pieces, giving you a wide range of SAE sizes for different materials. The case is 8.7 inches tall, which is taller than the 1.8-inch height of the Bosch CO14B case, so it may not fit as easily in shallow drawers. It uses titanium-coated HSS steel for durability, a general-purpose choice for wood, metal, and drywall.

The Bosch CO21 set features a no-skate split-point tip, which bites into metal without wandering for clean, precise starts. This accuracy is key for fabricators drilling tough materials like stainless steel or cast iron, where hole placement must be exact. Bits 3/16-inch and larger have a three-flat shank that locks securely in the chuck, reducing slippage when pushing through hard stock. The included sizes range from 1/16-inch to 1/2-inch, providing a wide selection for various drilling tasks in metal, wood, and plastic.

A controlled test drilling 6mm stainless steel measured durability. In that test, a Bosch cobalt bit drilled 15 holes, while the top-performing bit drilled 135 holes. For a user drilling hundreds of holes in hard metal daily, that lifespan difference could influence the purchase. The Bosch bits are manufactured from cobalt for drilling in hard and abrasive materials and provide 4X longer life than standard high-speed drill bits, according to the manufacturer. If the primary goal is maximum holes per bit in tough alloys, research indicates a specialist like the Adiseal Ultimate drilled more holes in that specific test.