Best Drill Bit Set for Metal (2026): Cobalt and HSS Picks That Bite
Drills and drivers
The best drill bit set for metal is the DEWALT DWA1181, a 21-piece black and gold oxide set that runs from 1/16 to 1/2 inch and covers mild steel, sheet metal, and bracket work. Add a MACXCOIP M35 cobalt set for stainless, or the compact DEWALT DWA1184 for a set that lives in the drill bag.
Our picks
The best drill bit set for metal is the DEWALT DWA1181, because it covers the sizes a home shop actually uses and its 135-degree split point starts cutting where you mark instead of skating across the surface. Most metal drilling is ordinary work: pilot holes for bolts, clearance holes in brackets, holes in tube and angle.
You do not need a machine-shop index for that. You need bits that grip, cut cool, and survive a crowded drawer. The other half of the job is speed, and the rpm table below is the part most buying guides leave out.
Our drills and driver guides cover the rest of the kit, and the cordless drill guide pairs with any set here if you still need the tool. A mechanics tool set covers the wrenches and sockets around the job, and an impact driver handles the fasteners once the holes are drilled.
What a metal drill bit set actually has to do
Metal is harder on a bit than wood, so two things matter more than the number of pieces in the case. The tip has to start on contact, and the shank has to hold in the chuck without slipping. A 135-degree split point handles the first job. The three-flat shank handles the second on the larger sizes.
What does the 135-degree split point actually do?
A split point grinds the tip so the chisel edge becomes a point that bites on contact instead of skating. That is why a center punch is optional on flat mild steel. On round or polished stock, a light punch still helps.
118 or 135 degree point: which should you buy?
A 135 degree split point is the better choice for hand drilling, because it bites on contact and needs less push. A 118 degree point is the older general-purpose grind, and it walks across smooth steel unless you center punch first.
The trade is edge strength. The thinner 135 point has less metal behind the tip, so it dulls a little faster in abrasive material. For sheet metal, brackets, and anything drilled with a hand-held tool, that trade is worth it. For a drill press and thick plate, a 118 point is fine.
Why do the 3-flats shanks matter?
A 3-flats shank is a round shank with three ground flats, not a proprietary lock. On the DEWALT sets the flats start at 13/64 inch and go up, so the larger bits grip a three-jaw keyless chuck and resist the spin-out that rounds a shank.
Coating is the other decision. Black and gold oxide resists rust and is cheap, but it is not a hardness coating. Titanium nitride adds some surface life in mild steel. Cobalt is the one to buy if you drill stainless, hardened bolts, or cast iron, because the alloy stays hard when the bit gets hot.
Finally, keep the bits cool. Slow speed, steady pressure, and a drop of oil turn a cheap set into a good one. Run a bit wide open with no lubricant and even cobalt will give up.
What speed should you drill steel at?
A 1/4 inch high-speed steel bit in mild steel wants about 1,200 rpm, a 3/8 inch bit about 810, and a 1/8 inch bit about 2,400. Stainless takes roughly a third of those numbers, so the same 1/4 inch bit runs near 460 rpm.
The formula behind the table is the one machinists use: rpm = 3.82 x surface speed / bit diameter, with the surface speed in feet per minute. High-speed steel runs 80 to 100 feet per minute in mild steel and 30 to 50 in stainless. Because the diameter is on the bottom of the fraction, halving the bit size doubles the rpm.
Most cordless drills top out around 1,500 to 2,000 rpm in high gear and 400 to 600 in low gear, which tells you two things. A 1/4 inch hole in mild steel belongs in low gear with a firm trigger, and a 1/8 inch bit in mild steel is the one size a cordless drill cannot slow down enough, so ease off the trigger.
How fast should the drill feed?
Feed per revolution is roughly one to three percent of the bit diameter, so a 1/4 inch bit takes 0.004 to 0.008 inch per turn. That is a steady, firm push, not a shove. Fine dust instead of spiral chips means the bit is rubbing, and rubbing is what dulls an edge.
How many holes will one bit drill?
A 1/4 inch bit out of the $17.98 DWA1181 set costs about 86 cents. If it drills 200 holes in 1/8 inch mild steel with oil before it dulls, that is less than half a cent per hole, which is why replacing a bit beats fighting a dull one.
Treat 200 as a planning number, not a guarantee. Plate thickness, pressure, and coolant move it a lot, and a bit run dry at 2,000 rpm in stainless may not finish ten holes. The point is the ratio: the bit is the cheapest part of the job, so a sharp one is always the better choice.
Top pick: DEWALT DWA1181 21-piece
The DEWALT DWA1181 is the best drill bit set for metal for most people because it is honest about what it is. It is a general-purpose high-speed steel set with a black and gold oxide finish, sold in 21 sizes from 1/16 to 1/2 inch, and it does the everyday jobs well. The parabolic flute with a 31 degree helix clears chips without the aggressiveness of a true parabolic bit.
What is actually in the 21-piece set?
The set runs 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 11/64, 3/16, 13/64, 7/32, 15/64, 1/4, 5/16, 3/8, and 1/2 inch, with spares in the sizes that wear out first: two each of 1/16, 5/64, 1/8, 3/16, and 1/4 inch. The 1/2 inch bit carries a 3/8 inch shank so it fits a standard chuck.
That spare-bit detail matters more than it sounds. The 1/8 and 3/16 bits are the ones that snap when a hole is widened by side-loading, and having a second one in the case is the difference between finishing the job and driving to the store.
What does the set cost per bit?
At $17.98 for 21 bits the DWA1181 works out to about 86 cents per bit, and the set covers 1/16 inch up to 1/2 inch. That is the everyday range for pilot holes, bracket bolts, and conduit fittings.
The 135-degree split point is the reason to choose it over a cheap hardware-store index. It bites on the mark and resists walking, which is the difference between a clean hole and a scratched-up bracket. The 3-flats shank and the tapered web add rigidity, so the larger bits do not spring or spin when you lean on the drill.
This is not a stainless set. For that, step up to cobalt, which is the next pick. What this set gives you is range, reliability, and a price that leaves money for the bits that matter in hard metal.
Who it is for: Homeowners and DIYers who drill mild steel, sheet metal, aluminum, wood, and plastic, and want one set that covers the common sizes.
Skip if: You mostly drill stainless steel or hardened bolts, where a cobalt set is the right first buy.
Shop: DEWALT DWA1181 on Amazon
Best for stainless and hardened steel: MACXCOIP M35 cobalt
The MACXCOIP M35 cobalt set is the best pick for anyone who drills stainless steel, hardened bolts, or cast iron. M35 cobalt is about 5 percent cobalt, which makes the alloy noticeably harder than plain HSS. That hardness is what lets the bit keep cutting when a black oxide bit would heat up and dull.
What does cobalt cost per bit?
The MACXCOIP 13-piece set works out to about 69 cents per bit at $8.98, cheaper per bit than the larger HSS set. The trade is range: it stops at 1/4 inch and the smallest bits are delicate.
Treat cobalt with respect and it lasts. Run it slow, press hard, and use a drop of cutting oil. In stainless that means about 460 rpm on a 1/4 inch bit rather than the 1,200 rpm the same size wants in mild steel, which is the mistake that blues a cobalt edge. The 135-degree split point keeps the bit centered so you spend less time chasing a wandering hole.
The set runs from 1/16 inch to 1/4 inch, which covers pilot holes and most bolt clearances. It is not the set for big holes.
Who it is for: Home mechanics, fabricators, and anyone who drills stainless, hardened bolts, or cast iron, and wants cobalt performance without a pro-shop price.
Skip if: You only drill mild steel and wood, where the DEWALT sets cover you for less.
Shop: MACXCOIP M35 cobalt set on Amazon
Best compact set: DEWALT DWA1184 14-piece
The DEWALT DWA1184 is the best compact set for a drill bag or a tight bench. It is the same family as the top pick, with the same 135-degree split point and 3-flats shank, but trimmed to the 14 sizes most people wear out and packed into a small index.
What is actually in the 14-piece set?
The set runs 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8, and 1/2 inch, with a spare 1/8 inch bit. That is 14 pieces in a case the size of a paperback.
It skips the 1/64 steps between 1/4 and 3/8 inch, so 13/64, 15/64, 17/64, and 9/32 are missing. For bracket bolts and pilot holes that does not matter, and it is the reason the case is small enough to live in the bag.
What does the 14-piece set cost per bit?
At $12.98 for 14 bits the DWA1184 works out to about 93 cents per bit, and it carries the same 135-degree split point and 3-flats shank as the larger DEWALT set.
The 3-flats shank is the detail we like most. It is not a proprietary lock, it is a round shank with three ground flats, so it grips harder in any three-jaw keyless chuck and resists the spin-out that rounds a shank. That matters most on the 1/4 and 5/16 sizes when you lean into a hole.
The split point also helps on curved stock. On one-inch pipe or a rounded bracket, the point catches the high spot and stays there instead of skating down the curve. If you already own a few singles, this is the set to refill around.
Who it is for: Anyone who wants a grab-and-go set for pilots, small clearance holes, and drill-outs, and does not want a big index taking up shelf space.
Skip if: You need every 1/64 size, or you drill stainless often and need cobalt.
Shop: DEWALT DWA1184 on Amazon
How the three sets compare
The 21-piece DEWALT is the do-everything set. The cobalt MACXCOIP is the one you reach for when the metal gets hard. The 14-piece DEWALT is the compact set that stays with the drill.
Which drill size goes with which bolt?
The reason to own a fractional set is taps and clearance holes. A tap drill leaves the right amount of thread, and a clearance hole lets the bolt pass through the first plate. Both need a specific size, and neither is the same as the bolt diameter.
The 21-piece DEWALT set covers every clearance hole in that table and the 5/16 and 3/8 tap drills. The cobalt set covers the #7 and #25 tap drills and the 13/64 clearance, which is why the two sets work as a pair rather than as alternatives.
Cobalt vs black oxide vs titanium
The coating decides which metal the bit is happy in, so match it to the job instead of buying the biggest box.
If you drill metal more than a few times a year, the honest answer is to own both. Keep a general HSS set for wood, plastic, and mild steel, and a cobalt set for the jobs that ruin cheap bits.
How to drill metal without burning bits
Start with a center punch on anything round or polished. Even a split point likes a small dimple to sit in, and it stops the bit walking on smooth stock.
Run the drill slow. Most cordless drills have plenty of speed for metal and too much for the bit. Low gear, steady pressure, and a drop of cutting oil keep the temperature down, which is what saves the edge.
Let the bit cut. If you are pushing hard and seeing fine dust instead of spiral chips, the bit is rubbing. Ease up, slow down, and add oil. Ease off the trigger as you break through so the bit does not catch and snap.
Why does a pilot hole make a big hole easier?
A pilot hole removes the center of the cut, so the big bit only has to enlarge a hole instead of boring through solid steel. Step up about one size at a time, and use the largest pilot the final bit can follow. On a 1/2 inch hole, a 1/4 inch pilot halves the material the big bit removes.
Who should skip these sets
Skip all three if you drill concrete or masonry. Those jobs need a hammer drill and carbide bits, and twist bits will just spin and overheat.
Skip the cobalt set if your work is almost all wood, plastic, and mild steel. You would pay more for hardness you never use, and the DEWALT 21-piece covers that work for less.
Skip the compact set if you need every 1/64 size, or if you drill stainless often. A 13/64 hole is a real size in machine work, and the compact set has a gap there on purpose.
Buy the set that matches the metal you actually drill, then spend the savings on oil and a good center punch.
Bottom line: The best drill bit set for metal is the DEWALT DWA1181 for mild steel, sheet metal, and everyday work, the MACXCOIP M35 cobalt set for stainless and hardened bolts, or the DEWALT DWA1184 14-piece kit for a compact set that stays with the drill. Run a 1/4 inch bit near 1,200 rpm in mild steel and near 460 in stainless, and the bits will outlast the job. More shop guides live on the Workshoppicks blog and the drills and driver guides page.
Frequently Asked Questions
What is the best type of drill bit for drilling through metal?
For mild steel, sheet metal, and bracket work, a high-speed steel twist bit with a 135-degree split point does the job. For stainless steel, hardened bolts, or cast iron, use a cobalt bit. The split point matters more than the brand because it starts cutting on the mark instead of walking across the surface.
What speed should I drill metal at?
A 1/4 inch high-speed steel bit in mild steel wants about 1,200 rpm, and a 3/8 inch bit about 810 rpm. Stainless wants roughly a third of that, so the same 1/4 inch bit runs near 460 rpm. The shop rule is rpm equals 3.82 times the surface speed divided by the bit diameter in inches.
Are cobalt or titanium drill bits better for metal?
Cobalt is the better choice for hard metal. M35 cobalt is harder than titanium and black oxide, so it holds an edge in stainless and heat-treated steel. Titanium-coated bits last longer than plain black oxide in mild steel but still soften on stainless. If you drill metal often, own a cobalt set.
What is the best drill bit brand for metal?
DEWALT, Milwaukee, and Irwin all make dependable high-speed steel and cobalt sets. For a home shop, DEWALT gives the widest coverage for the money, and the black and gold oxide sets are the ones most people already own. Budget cobalt sets from smaller brands are worth it for occasional stainless work.
Can I use black oxide bits on stainless steel?
You can, but you will not get far. Black and gold oxide is a corrosion coating, not a hardness coating, so the cutting edge dulls fast and the bit can blue in stainless. Use cobalt with oil and a slow speed instead.
What size drill bit set do I need for home metalwork?
A set from 1/16 inch to 1/2 inch covers almost everything a home shop drills, including pilot holes, bracket bolts, and conduit fittings. Both DEWALT sets here reach 1/2 inch, which is the size a 3/8 inch conduit connector wants. Add a step bit only if you drill sheet metal often.
Why do my drill bits burn or squeal in metal?
Heat is the usual cause. Running the drill too fast, pressing too little, or skipping lubricant lets the edge rub instead of cut, so it squeals and darkens. Slow the drill down, press firmly, and add a drop of cutting oil or a squirt of WD-40 to keep the bit cool.
Do I need a center punch with these bits?
A 135-degree split point starts on contact, so a center punch is optional on flat stock and mild steel. On round pipe, polished stainless, or a precise layout, a light center punch still helps you start the hole exactly where you marked it.
What is the difference between a 118 and a 135 degree drill point?
A 118 degree point is the older general-purpose grind and it walks on smooth steel unless you center punch first. A 135 degree split point flattens the tip and adds a secondary grind, so it bites on contact and needs less pressure. For sheet metal and hand-held drilling, 135 is the easier point.