Best Drill Bits: Start With HSS, Then Add the Right Specialists

For mixed DIY work with a conventional drill/driver, start with a modest high-speed steel (HSS) twist-bit set. Add brad points for precise wood holes, cobalt bits for demanding metal work, and purpose-built masonry or tile bits when the project calls for them. A bigger twist-bit case is not a substitute for those different cutting designs.

The recommendations below are an application-based shortlist, not a hands-on performance ranking. Product specifications were checked on October 5, 2026; we have not measured comparative drilling speed, hole accuracy or bit life.

Mixed DIY work: DeWalt DWA1184 HSS set

The DWA1184 is a sensible starting point if you drill wood, plastic and metal rather than one demanding material repeatedly. DeWalt specifies HSS construction, a 135-degree split point intended to reduce wandering, and three-flat shanks intended to reduce slipping in the chuck. It lists the set as standard, rather than impact-rated. DeWalt’s specifications support those applications—not a claim that it outlasts competing sets.

Its contents illustrate why you should read the size list rather than the piece count: 14 bits means 13 distinct diameters, because the 1/8-inch bit is duplicated. Sizes run from 1/16 to 1/2 inch, but there are gaps, including 9/32 and 7/16 inch.

Choose it for: a first general-purpose set with useful small diameters and a spare 1/8-inch bit.

Choose something else when: you need precise woodworking holes, a specific tap-drill diameter, masonry drilling or impact-driver use. Buy those missing capabilities separately.

Precise wood holes: a brad-point set

For dowelling and cabinetry, prioritize a brad-point design over upgrading a general twist-bit set’s coating. Century’s seven-piece brad-point set is a documented option: the manufacturer specifies heat-treated HSS, a self-centering tip, and use in hand drills and drill presses. Its stated applications include furniture making, cabinetry and dowelling. The fractional set contains 1/8, 3/16, 1/4, 5/16, 3/8, 7/16 and 1/2-inch bits. Century’s product details establish that intended use, not independently measured fit accuracy.

Choose it for: a spread of woodworking diameters you expect to use.

Buy individually instead when: the project needs only one dowel size or a metric diameter absent from the fractional set. For technique and exit-hole considerations, see our brad-point guide.

Stainless steel and demanding metal work: Milwaukee RED HELIX cobalt

Milwaukee’s RED HELIX cobalt range is a candidate when stainless steel, cast iron or thick metal is the recurring job. The manufacturer explicitly lists those applications and specifies drill/driver use. Its 29-piece set, model 48-89-2332, uses a variable-helix flute, a tapered web and three-flat shanks. Milwaukee’s product page describes those features and applications.

Choose it for: a metal-focused kit, rather than paying for cobalt primarily to drill occasional wood holes.

Buy individually instead when: you need only one or two metal-hole sizes. Do not read “hard metal” as a blanket hardened-steel rating; confirm that the exact bit suits the alloy and hardness. Our cobalt drill-bit guide covers selection and operating settings.

Thin sheet metal: IRWIN UNIBIT #1

A step bit is worth adding when you need several hole diameters in thin material. The IRWIN UNIBIT #1, model 10231, covers 1/8 to 1/2 inch in 1/32-inch increments. IRWIN specifies HSS construction and lists thin stainless steel, copper, brass, aluminum, plastic and laminates as applications. IRWIN’s specifications support that role.

Choose it for: several sizes of shallow through-holes without repeatedly swapping bits.

Skip it when: you need a deep, constant-diameter bore. Check the permissible workpiece thickness for the exact step bit; the marked diameter range alone does not establish drilling depth. See what a step drill bit is used for.

Masonry and concrete: choose the shank system first

There are two distinct purchases here:

• For a conventional hammer drill/driver: Bosch BlueGranite Turbo bits have carbide tips and hex shanks compatible with standard three-jaw chucks. Bosch explicitly rates this range for hammer drill/drivers and impact drivers. Its HCBG500T set contains 1/8, 3/16, 1/4, 5/16 and 3/8-inch sizes. Bosch’s specifications explain the compatibility.
• For an SDS-plus rotary hammer: Bosch Bulldog Xtreme bits have a four-cutter, full-carbide head and an SDS-plus shank. Bosch specifies SDS-plus rotary-hammer use and lists cutting diameter, working length and total length separately. Bosch’s product table lets you select the actual hole size and usable reach.

For an anchor installation, buy the diameter and working length needed to meet the anchor’s hole-depth instructions. Do not choose a nearby diameter merely because it is already in the case: for example, Simpson Strong-Tie’s Titen Turbo instructions specify the drill diameter and warn that oversized holes reduce load capacity.

Porcelain tile: a specifically rated diamond bit

Bosch’s DDB3PC diamond set is an option for small holes in porcelain and natural-stone tile. It contains two 1/4-inch bits and one 5/16-inch bit, uses cylindrical shanks for three-jaw chucks, and is designed for dry drilling with a built-in wax cooling insert. Bosch’s specifications distinguish it from bits requiring water.

Choose it only if those diameters fit the job. Otherwise, buy the correct individual size. Tile drilling calls for rotary operation, not hammer action. If masonry lies underneath, change to a masonry bit after penetrating the tile. Bosch’s tile-drilling guidance explains that work sequence. Our porcelain drilling guide covers the remaining selection checks.

Set or individual bits?

Buy a set for the material you drill regularly; buy individual specialist bits for occasional projects. Before ordering, verify cutting diameter, shank fit, working depth, material rating and permitted operating mode. Those five checks matter more than the number of pieces—or the color of the coating.