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Choosing the Best Drill Bits For Hardened Steel can save a lot of frustration when you need clean, reliable drilling through tough materials. The products below are selected from the provided list and cover a range of budgets, sizes, and use cases, from compact stubby sets to larger index kits for hard metals and stainless steel.
When comparing options, pay close attention to the material type listed, the size range, the bit count, and the product rating. If you need a general-purpose set, a broader assortment may be best. If you mostly work in tight spaces, a stubby or hex-shank option may be more practical. Price also matters, but the best value often comes down to having the right sizes and a set that matches your drilling needs.
Let’s get started!
Our Top Picks at a Glance
| Product | Best For | Buy Now |
|---|---|---|
| Cobalt Drill Bit Set – 29Pcs M35 High Speed Steel Twist Drill Bits | Best overall all-around set for hardened metals and stainless steel | Buy |
| BOSCH CO14B 14-Piece Cobalt M42 Metal Drill Bits | Best premium compact brand-name option for hard metals | Buy |
| DEWALT 21 Pc. Titanium Nitride Coated Pilot Point Drill Bit Set | Best value general-use set with strong ratings | Buy |
Best Drill Bits For Hardened Steel
1. Best Overall: Cobalt Drill Bit Set – 29Pcs M35 High Speed Steel Twist Drill Bits
This 29-piece cobalt drill bit set is a strong all-around choice for users looking for one of the best drill bits for hardened steel in a practical size range. It is listed as M35 high speed steel and is designed for hardened metals, stainless steel, cast iron, and wooden plastics.
The set includes sizes from 1/16″ to 1/2″, which gives it broad usefulness for many common drilling tasks. The included metal index storage box also makes it easier to keep the bits organized and ready to use.
With a 4.5 rating and a mid-range price, it stands out as a balanced option for buyers who want a versatile kit without jumping to a much higher price point.
Pros
- 29-piece size range
- Designed for hardened metals and stainless steel
- Includes metal index storage box
- Strong 4.5 rating
Cons
- Higher price than some smaller sets
- May be more than casual DIY users need
2. Best Premium Pick: BOSCH CO14B 14-Piece Cobalt M42 Metal Drill Bits
The BOSCH CO14B set is a 14-piece cobalt M42 drill bit assortment aimed at stainless steel, cast iron, titanium, and light-gauge metal. For shoppers who prefer a smaller branded set, this is a dependable option with a clear metal-drilling focus.
Its three-flat shank design may appeal to users who want a more secure fit in the chuck. The included case also helps keep the set organized when moving between jobs.
With a 4.6 rating and a more affordable price than many cobalt sets, it offers a nice mix of brand reputation and practical design for hard-material drilling.
Pros
- Cobalt M42 construction listed
- Three-flat shank design
- Includes case
- 4.6 rating
Cons
- Only 14 pieces
- Not as broad a size selection as larger kits
3. Best Value: DEWALT 21 Pc. Titanium Nitride Coated Pilot Point Drill Bit Set
This DEWALT 21-piece set is one of the most affordable options in the list and carries a strong 4.8 rating. It is listed for wood, metal, and plastic, making it a flexible general-purpose set for everyday use.
The titanium nitride coating and pilot point design are part of the product listing, and the included case adds portability and organization. While it is not described as a dedicated hardened steel set, it remains a popular budget-conscious choice for mixed-material tasks.
If you want strong ratings, a recognized brand, and a low entry price, this set delivers excellent value for many users.
Pros
- Very affordable price
- 4.8 rating
- 21-piece set
- Includes case
Cons
- Not specifically described as cobalt
- Less specialized for hardened steel than some other options
4. Best Larger Cobalt Set: Cobalt Drill Bit Set – 29Pcs M35 HSS Twist Drill Bits
This 29-piece M35 cobalt set is another strong option for hardened metals, stainless steel, cast iron, and wooden plastics. The size range from 1/16″ to 1/2″ makes it useful for a wide variety of drilling jobs.
The metal index storage box is a practical touch for keeping bits sorted and easy to access. For shoppers who want a set with a broad assortment and a familiar format, this is an attractive choice.
It is priced similarly to other premium cobalt kits, and the 4.0 rating suggests it may be a fit for buyers focused on size coverage and material listing.
Pros
- 29-piece assortment
- Broad size range
- Includes metal index storage box
- Suitable for hardened metals and stainless steel
Cons
- 4.0 rating is lower than some alternatives
- Price is relatively high
5. Best Large Set: Cobalt Drill Bit Set for Hardened Metal and Stainless Steel, 99Pcs
This 99-piece cobalt M35 set is built for buyers who want a large assortment for hardened metal and stainless steel work. The range from 1/16″ to 3/8″ makes it a practical jobber-style kit for many common sizes.
The plastic index storage case helps organize the large number of bits, which can be especially useful on busy job sites or in workshops. With a 4.5 rating, it looks like a solid choice for users who want breadth over a smaller specialized kit.
If you need more size coverage and prefer not to run short on common bit sizes, this is one of the more comprehensive picks on the list.
Pros
- Very large 99-piece set
- Designed for hardened metal and stainless steel
- Includes plastic index storage case
- 4.5 rating
Cons
- Higher price
- Size range tops out at 3/8″
6. Best Premium Heavy-Duty Option: Drill America 29 Piece Cobalt Stepped Point Drill Bit Set
This Drill America set is listed as a 29-piece cobalt stepped point drill bit set with a gold oxide finish. It is designed for acrylic, steel, and hard metals, with sizes from 1/16″ to 1/2″ by 64ths.
The round case is included, and the expanded size sizing by 64ths may appeal to users who need more detailed size control. However, the price is significantly higher than many other sets on the list.
For users who specifically want a premium-priced set with a broad size range and hard-metal listing, it is a notable option.
Pros
- 29-piece set
- Size range from 1/16″ to 1/2″ by 64ths
- Includes round case
- Designed for hard metals
Cons
- Much more expensive than most alternatives
- 3.8 rating is lower than several competitors
7. Best Heavy-Duty Budget Pick: Drill America KFD29J-PC 29 Piece HSS Drill Bit Set
The Drill America KFD29J-PC set is a 29-piece heavy-duty high speed steel drill bit kit with a black and gold finish. It covers sizes from 1/16″ to 1/2″ by 64ths and comes in a round case.
The product listing positions it for heavy-duty use, and the size range makes it a flexible choice for general drilling needs. At its price point, it is less expensive than some premium cobalt options while still offering a substantial assortment.
Its 4.5 rating gives it a solid standing for buyers who want a traditional HSS kit with dependable size coverage.
Pros
- 29-piece heavy-duty set
- Includes round case
- Size range from 1/16″ to 1/2″ by 64ths
- 4.5 rating
Cons
- Not specifically listed as cobalt
- Higher price than some budget sets
8. Best Compact Set: M35 Cobalt Drill Bit Set 20PCS
This 20-piece M35 cobalt set is a compact option for users who still want coverage from 1/16″ to 1/2″. It is listed for hardened metal and includes an index storage case for organization.
Jobber length bits are a familiar format for many drill users, and this set focuses on the essentials without reaching into a very large piece count. That makes it attractive for those who want a more manageable kit.
Its lower price point and 4.4 rating help it stand out as a practical smaller set for the budget-minded buyer.
Pros
- Compact 20-piece set
- Size range from 1/16″ to 1/2″
- Includes index storage case
- Affordable price
Cons
- Fewer bits than larger sets
- Not as broad an assortment as 29- or 99-piece kits
9. Best Organised Round-Case Set: CaRoller Cobalt Drill Bit Set 29-Piece
The CaRoller 29-piece cobalt drill bit set is listed for steel, wood, plastic sheet metal, and other materials. It uses a durable round shank design and includes a practical cup-type holder.
With a 4.6 rating, it is one of the better-rated sets in the collection. The cup-style holder may be especially useful for users who want quick access without a traditional flat storage case.
For buyers who value a basic but organized 29-piece set and a strong customer rating, this is an appealing choice.
Pros
- 29-piece set
- Includes practical cup-type holder
- 4.6 rating
- Listed for steel and sheet metal
Cons
- Not the lowest price
- Storage style may not suit everyone
10. Best Stubby Option: NordWolf 5-Piece M35 Cobalt Stubby Drill Bit Set
The NordWolf stubby set is designed for stainless steel and hard metals and includes a 1/4″ hex shank for quick chucks and impact drivers. Its compact, short profile is ideal for tight spaces.
This is a five-piece SAE set, so the range is limited, but the included storage box and hex-shank compatibility make it practical for certain tasks. It is also one of the lower-priced options in the lineup.
If you need a small, easy-to-handle set for select sizes and tighter access, this one has a clear purpose.
Pros
- Stubby design for tight access
- 1/4″ hex shank
- Compatible with quick chucks and impact drivers
- Affordable price
Cons
- Only 5 pieces
- Limited size selection
11. Best Mid-Range Cobalt Set: Cobalt Drill Bit Set, 29Pcs M35 High Speed Steel Bits
This 29-piece M35 cobalt set offers a familiar layout with sizes from 1/16″ to 1/2″ and a metal index storage box. It is listed for hardened metals, stainless steel, cast iron, and wooden plastics.
The 4.4 rating suggests a well-received product, and the overall format will feel familiar to anyone looking for a standard drill bit assortment with hard-metal applications.
It sits in the middle of the price range and can work well for users who want a balanced set without going to the highest-end price tags.
Pros
- 29-piece assortment
- Metal index storage box included
- Broad size range
- Suitable for hard metals and stainless steel
Cons
- Price is still relatively high
- 4.4 rating is good but not the highest
12. Best Simple General-Use Set: DEWALT 14-Piece 3-Flats Shank Drill Bit Set
This DEWALT 14-piece set is listed for plastic, wood, and metal, and it includes a 135-degree split point along with a 3-flats shank. It is one of the least expensive picks in the group.
The product is not specifically marketed as a hardened steel set, but it may still appeal to users who want a compact general-purpose kit from a recognizable brand. The 4.8 rating is a strong sign of customer satisfaction.
For light-duty to general drilling tasks, this set is easy to recommend as a low-cost option.
Pros
- Very low price
- 4.8 rating
- 3-flats shank
- Compact 14-piece set
Cons
- Not specifically made for hardened steel
- Smaller set size
13. Best Large Mixed-Size Set: HIDOTOL 115PCS Cobalt Drill Bit Set
The HIDOTOL 115-piece set offers the largest assortment on the list, with fractional sizes from 1/16″ to 1/2″, letter sizes A-Z, and wire sizes #1 to #60. It is listed as M35 HSS for hardened steel and includes an indexed metal case.
This is a strong option for users who need a very broad selection and want multiple sizing systems in one kit. The 4.4 rating and large piece count make it especially appealing for workshop use.
If your priority is having many sizes on hand, this set is one of the most complete choices available here.
Pros
- Huge 115-piece set
- Fractional, letter, and wire sizes included
- Indexed metal case
- Listed for hardened steel
Cons
- Higher price
- May be more than many users need
14. Best Coated Pro Set: toolant Cobalt Drill Bit Set for Metal and Steel
The toolant Pro set is listed as a cobalt drill bit set for metal and steel with Titanium Aluminum Nitride coating and a bullet point tip. It is designed for hardened metal and stainless steel, with 21 pieces from 1/16″ to 1/2″.
This combination of coated surface and bullet point tip gives it a distinct place among the products listed, especially for users looking for a more specialized 21-piece set. The 4.3 rating is respectable, and the price is lower than many large cobalt kits.
For buyers who want a coated option with a focused set size, this is a compelling mid-range entry.
Pros
- TiAlN coated
- Bullet point tip listed
- 21-piece size range
- Designed for hardened metal and stainless steel
Cons
- Not the highest rating in the list
- Fewer pieces than larger sets
15. Best Indexed Round-Case Set: HIDOTOL Cobalt Drill Bit Set 29 PCS
This HIDOTOL 29-piece set is listed as M35 high speed steel twist jobber drill bits for hardened metal, stainless steel, cast iron, plastic, and wood. It includes an indexed round case and covers sizes from 1/16″ to 1/2″ by 1/64ths.
The detailed sizing and included case make it a useful everyday assortment. Its 4.4 rating suggests it is a well-liked option among buyers looking for a practical cobalt kit.
As a final pick, it offers a familiar 29-piece format with a durable storage solution and a wide enough range to suit many users.
Pros
- 29-piece set
- Indexed round case included
- Sizes from 1/16″ to 1/2″ by 1/64ths
- Listed for hardened metal and stainless steel
Cons
- Price is not the lowest
- May overlap with other similar 29-piece sets
Buying Guide
Shopping for the best drill bits for hardened steel means balancing material, size range, and the type of jobs you plan to tackle. Below are the most important points to keep in mind before buying.
Bit Material
The listings here include cobalt M35, cobalt M42, high speed steel, and titanium nitride coated options. For hardened steel, cobalt-labeled sets are commonly positioned for harder materials, while coated or standard HSS options may be better suited to broader everyday use.
Size Range
Consider whether you need a compact set or a wider assortment. Some products focus on a small number of bits, while others include extensive fractional ranges, letter sizes, and wire sizes. Choose based on the types of holes you drill most often.
Storage Case or Holder
Many of the listed products include an index storage box, round case, or cup-type holder. Good storage helps keep bits organized and easy to reach, especially if you use multiple sizes regularly.
Shank Type
Some products list a three-flat shank or a 1/4″ hex shank. These can matter if you want better grip in the chuck or compatibility with quick chucks and impact drivers.
Rating and Price
Ratings can help highlight user satisfaction, but price still matters. A more expensive set may offer more sizes, while a lower-cost option can be enough if you only need a few common bits.
Frequently Asked Questions
What are the best drill bits for hardened steel?
From this list, cobalt drill bit sets are the most directly positioned for hardened metals and stainless steel. Several M35 and M42 cobalt options are included, along with a few coated or heavy-duty sets.
Do I need cobalt drill bits for hardened steel?
Cobalt drill bits are commonly listed for hardened metal applications, so they are a strong place to start. If your work is lighter or more general-purpose, some non-cobalt sets on the list may still be useful.
Is a larger set always better?
Not necessarily. A large set gives you more size options, but a smaller set may be a better fit if you only use a few common sizes or want a more budget-friendly choice.
What should I look at first when comparing these products?
Start with the material listing, then check the size range, the rating, and the storage case. Those four points usually tell you whether a set will match your needs.
Are the DEWALT sets on this list made for hardened steel?
The DEWALT products listed here are general-use drill bit sets for wood, metal, and plastic. They are included because of their ratings and value, but they are not described in the same hardened-metal terms as the cobalt sets.
Conclusion
The best drill bits for hardened steel depend on how often you drill hard materials, how many sizes you need, and how much you want to spend. If you want a balanced all-around pick, the 29-piece cobalt sets are especially strong. If you want the lowest price, the DEWALT options stand out for value. For the broadest assortment, the HIDOTOL 115-piece set is the most expansive choice here.
No matter which option you choose, the key is to match the set to your actual workload. A well-chosen drill bit set can make hard-metal drilling much more manageable and help you get better results with less hassle.