Drilling through steel can be a challenging task without the right tools. Whether you’re a professional welder, a DIY enthusiast, or working on a tough metal fabrication project, having the best bits for drilling steel is crucial for efficiency and safety. Standard drill bits often dull quickly or break when encountering hard metals, leading to frustration and wasted time. This comprehensive guide will help you navigate the options, highlighting top-performing drill bits designed to tackle steel, stainless steel, and other robust alloys with precision and durability. We’ve rigorously tested and reviewed five exceptional sets to ensure you find the perfect match for your toughest drilling needs.
Quick Product Comparison
Our Top 5 Best Bits For Drilling Steel Reviews – Expert Tested & Recommended
1. DEWALT 21-Piece Titanium Nitride Coated Pilot Point Drill Bits for Drilling Steel
The DEWALT 21-Piece Titanium Nitride Coated Pilot Point Drill Bit Set is an exceptional choice for anyone needing to drill through steel with precision and longevity. These bits feature a robust Titanium Nitride (TiN) coating, enhancing their hardness and heat resistance, which is vital when working with demanding materials like steel. The innovative pilot point tip ensures accurate starts and cleaner holes, minimizing bit walking and improving drilling efficiency.
Key Features That Stand Out
- ✓ Titanium Nitride Coating: Provides increased durability, reduced friction, and superior heat resistance for extended bit life.
- ✓ Pilot Point Tip: Designed for clean, accurate starts on contact, preventing bit walking on hard surfaces.
- ✓ Optimized Flute Design: Facilitates efficient chip removal, reducing heat buildup and preventing clogging.
- ✓ Comprehensive Set: Includes a wide range of sizes (21 pieces) to cover most common drilling applications in steel.
Why We Recommend It
We recommend this DEWALT set for its outstanding blend of durability, precision, and value. The TiN coating significantly prolongs the life of the bits, especially when drilling tough materials, while the pilot point ensures that your holes start exactly where you intend them to. This set is a reliable workhorse for both professional tradespeople and serious DIYers.
Best For
This set is best for general-purpose drilling in steel, stainless steel, and other non-ferrous metals, ideal for construction, automotive repair, and fabrication projects where accurate hole placement is essential.
Pros and Cons
Pros:
- Excellent durability and heat resistance due to TiN coating.
- Pilot point tip provides precise, walk-free starts.
- Efficient chip removal prevents overheating.
- Wide range of sizes in a convenient case.
Cons:
- Not as resistant to extreme heat as pure cobalt bits for continuous heavy-duty use.
- Coating can wear off over time with abrasive materials.
Customer Reviews
Customer Review: “This is an excellent drill bit set from DeWalt. I’d been eyeing it for a long time, waiting for the price to drop, and it was definitely worth the wait. Once it went on sale, I picked it up, and I’m glad I finally did—great quality and performance.”
Customer Review: “As a professional fabricator, I rely on bits that can handle tough steel daily. These DEWALT pilot point bits consistently deliver clean holes and hold their edge remarkably well. A solid investment for any toolbox.”
2. toolant Cobalt Drill Bit Set for Hardened Steel, Titanium Aluminum Nitride Coated
The toolant Cobalt Drill Bit Set is specifically engineered for tackling hardened steel and other tough metals, making it our Editor’s Choice for its advanced coating and material composition. These bits are made from high-quality cobalt steel and further enhanced with a Titanium Aluminum Nitride (TiAlN) coating, which dramatically increases surface hardness to 89HRC and provides exceptional heat resistance. This combination ensures faster cutting and prolonged sharpness, even under extreme conditions.
Key Features That Stand Out
- ✓ Cobalt Steel Construction: M35 Cobalt alloy offers superior hardness and resistance to abrasion and high temperatures.
- ✓ Titanium Aluminum Nitride (TiAlN) Coating: Boosts surface hardness to 89HRC, delivering outstanding heat resistance and extended life.
- ✓ 21-Piece Set: A comprehensive selection of sizes from 1/16″ to 13/64″, with multiple duplicates of smaller, more frequently used sizes.
- ✓ Fast and Sharp Cutting: Designed to maintain sharpness longer and cut efficiently through hardened materials.
Why We Recommend It
The toolant Cobalt Drill Bit Set stands out due to its professional-grade construction and advanced TiAlN coating. This combination ensures that the bits can withstand the immense heat and friction generated when drilling through hardened steel, cast iron, and other demanding alloys. It’s a robust set that offers longevity and consistent performance for serious metalworking.
Best For
This set is ideal for professionals and serious hobbyists who regularly work with hardened steel, stainless steel, cast iron, and other exceptionally tough metals where standard drill bits fail.
Pros and Cons
Pros:
- Excellent for hardened steel and exotic metals.
- Superior heat resistance from TiAlN coating and Cobalt content.
- Exceptional durability and long cutting life.
- Includes multiple common sizes for frequent use.
Cons:
- Higher price point compared to standard HSS bits.
- May require slower speeds and cutting fluid for optimal performance on very hard materials.
Customer Reviews
Customer Review: “I’ve been looking for a drill bit set that can truly handle hardened steel, and these toolant cobalt bits with the TiAlN coating are finally it! They cut through thick steel plates like butter, and I haven’t seen any signs of dulling after several uses.”
Customer Review: “Absolutely impressed with the heat resistance. I was drilling through some old, tough bolts and these bits stayed sharp and cool. The comprehensive size selection is a huge plus, too. A must-have for any serious metalworker.”
3. M35 Cobalt High-Speed Jobber Drill Bit Set for Hardened and Stainless Steel
The M35 Cobalt High-Speed Jobber Drill Bit Set offers remarkable quality and performance at a budget-friendly price point, making it our top pick for value. Crafted from M35 cobalt steel, these bits are specifically designed to be durable, sharp, and robust for cutting through tough materials like stainless steel, iron castings, and copper. With a 135-degree split point tip and twist design, they ensure quick and efficient drilling in both soft and hard objects.
Key Features That Stand Out
- ✓ M35 Cobalt Steel: Contains 5% cobalt, providing excellent heat and abrasion resistance for extended life.
- ✓ 135-Degree Split Point Tip: Facilitates self-centering and fast penetration, reducing the need for a pilot hole and preventing bit walking.
- ✓ Jobber Length: Standard length for versatile use in a wide range of applications.
- ✓ Versatile Sizes: Includes 13 common sizes from 1/16″ to 1/4″ to handle various tasks.
Why We Recommend It
This M35 Cobalt set provides professional-grade capabilities without the premium price tag. The cobalt alloy content ensures these bits can withstand the heat and friction of drilling tough metals far better than standard HSS bits. Its quick and efficient design makes it a reliable choice for everyday metal drilling challenges.
Best For
This set is best for DIY enthusiasts and professionals seeking a cost-effective yet highly capable solution for drilling through stainless steel, cast iron, and other challenging metals on an intermittent or regular basis.
Pros and Cons
Pros:
- Excellent value for M35 cobalt quality.
- Highly effective for drilling stainless steel and hardened metals.
- 135-degree split point prevents bit walking.
- Durable and robust for tough applications.
Cons:
- Some users reported occasional breakage on extremely tough jobs.
- May not offer the same longevity as M42 cobalt for continuous heavy industrial use.
Customer Reviews
Customer Review: “I had a use case where a machine screw had broken off in a location that wasn’t easy to access. I decided versus pulling the piece of equipment apart to improve access, I’d spend the money on a set of these with the hopes it would catch as I was drilling out the broken off screw. The screw broke d”
Customer Review: “I purchase this set just under a year ago. I have not use these drill bits but a couple of times and 4 have already broken.10/6/2025 Update. Macxcoip Cobalt Drill Bits set seller reached out address any issues or concerns in my satisfaction with the product I received. They offer a full refund or to”
4. BOSCH Cobalt M42 Metal Drill Bits with Three-Flat Shank for Drilling Stainless Steel, Cast Iron, Titanium.
The BOSCH Cobalt M42 Metal Drill Bits are premium-grade bits designed for superior durability and high-heat resistance, making them ideal for the toughest drilling applications. These jobber-length bits contain an enhanced M42 alloy material with 8% cobalt, which delivers significantly longer life (up to 10x more than standard bits) and exceptional resilience against high temperatures. The three-flat shank ensures a secure grip in drill chucks, preventing slippage.
Key Features That Stand Out
- ✓ M42 Cobalt Alloy (8% Cobalt): Provides superior hardness, wear resistance, and the highest heat resistance for drilling very hard metals.
- ✓ Three-Flat Shank: Prevents bit spin in the chuck, ensuring stable and efficient drilling.
- ✓ 10x Life vs. Standard Bits: Engineered for extended durability and performance, even in continuous use.
- ✓ Versatile Application: Excellent for stainless steel, cast iron, titanium, and other high-strength alloys.
Why We Recommend It
BOSCH is synonymous with quality, and these M42 Cobalt bits uphold that reputation. Their high cobalt content makes them exceptionally capable of handling intense heat and friction, which are common when drilling through hard metals like stainless steel. The three-flat shank is a practical feature that greatly enhances user experience by preventing slippage, ensuring consistent torque transfer.
Best For
These bits are best for demanding professional applications in metal fabrication, plumbing, HVAC, and automotive fields, particularly when frequently drilling stainless steel, cast iron, or titanium where maximum durability and heat resistance are paramount.
Pros and Cons
Pros:
- Exceptional heat resistance for prolonged use in hard metals.
- Superior longevity, outlasting many standard bits.
- Three-flat shank eliminates slippage in chuck.
- Reliable performance on stainless steel and exotic alloys.
Cons:
- Higher cost per bit compared to TiN or lower cobalt content bits.
- Can be more brittle if side-loaded or misused due to high hardness.
Customer Reviews
Customer Review: “Anything Bosch makes is good, but I feel like they have it down pat when it comes to stuff like twist drills and bits. The M42 cobalt keeps the drill from getting too hot and also acts as a ‘lubricant,’ both contributing to keeping a sharp cutting edge, giving it quality and ease of use. These factors are crucial for my work.”
Customer Review: “This is a great drill bit set. The reason I purchased this set is because I needed to drill and tap a hole in the end of a lawnmower engine crankshaft. Rather than buying just that drill bit I decided to get a whole set, because I knew I would need drill bits again. I decided to go with this set over others for its reputation for toughness.”
5. M35 Cobalt Drill Bit Set with 1/4″ Hex Shank for Drilling Stainless Steel and Hard Metals
The M35 Cobalt Drill Bit Set with 1/4″ Hex Shank is specifically designed for versatility and access in tight spaces, making it an excellent choice for a wide array of users. Made from high-quality M35 Cobalt steel, these precision-ground drill bits offer extra durability and a long lifetime when drilling through challenging materials like stainless steel, cast iron, titanium, bronze, and aluminum. The 1/4″ hex shank is perfect for quick-change drill chucks and impact drivers.
Key Features That Stand Out
- ✓ M35 Cobalt Steel: Ensures high heat resistance and extended durability for drilling hard metals.
- ✓ 1/4″ Hex Shank: Provides secure grip and quick changes in impact drivers and standard drill chucks.
- ✓ Stubby Design: Short length (1.84 to 2.32 inches) allows access to hard-to-reach and tight spaces.
- ✓ 135° Split Point Multi-Blade: Promotes fast, clean drilling and prevents bit walking.
Why We Recommend It
This M35 Cobalt set shines with its practical design features, especially the 1/4″ hex shank and stubby length. It combines the robust performance of cobalt steel for hard metal drilling with the convenience and versatility needed for various projects, including those in confined areas. The precision-ground tips ensure consistent, high-quality holes.
Best For
This set is best for tradespeople and DIYers who need to drill stainless steel and other hard metals in constrained or awkward spaces, as well as those who prefer the convenience of quick-change hex shanks for impact drivers.
Pros and Cons
Pros:
- Ideal for tight and hard-to-reach areas due to stubby design.
- 1/4″ hex shank is compatible with impact drivers and quick-change chucks.
- Effective for drilling a wide range of hard metals.
- Durable M35 cobalt steel construction.
Cons:
- Shorter length may not be suitable for deep hole drilling.
- Impact drivers can increase the risk of bit breakage if not used with care.
Customer Reviews
Customer Review: “Ok drill bits for medium jobs, get the job done but don’t be to rough or will brake”
Customer Review: “A must have especially for tight areas. I had to drill out a bolt that broke off when replacing a thermostat. This thing cut thru like butter. Make sure to use steady pressure and a drill set on slow speed so it can grip and you will be thru in no time. Definitely recommend.”
Complete Buying Guide for Best Bits For Drilling Steel
Essential Factors We Consider
When selecting the best bits for drilling steel, several critical factors come into play. Understanding these elements will help you make an informed decision and ensure your drill bits perform optimally.
- Material Composition: The most crucial factor. For steel, you’ll primarily look at High-Speed Steel (HSS), Cobalt (M35 or M42), and Carbide. HSS is suitable for softer steels, while Cobalt bits (containing 5-8% cobalt) are superior for hard and stainless steel due to their excellent heat and abrasion resistance. Carbide bits are the hardest but also the most brittle and expensive, typically reserved for very specific, extreme applications.
- Coatings: Coatings like Titanium Nitride (TiN) or Titanium Aluminum Nitride (TiAlN) further enhance a bit’s performance. TiN increases surface hardness and reduces friction, extending bit life. TiAlN offers even greater hardness and heat resistance, making it ideal for high-temperature drilling in hardened steel.
- Point Angle: A 135-degree split-point tip is highly recommended for drilling steel. This design prevents “walking” on the material, allows for a self-centering start, and requires less force to penetrate, leading to cleaner, more accurate holes.
- Shank Type: Standard round shanks are common, but three-flat shanks or hex shanks offer better grip in the drill chuck, preventing slippage, especially with high torque. Hex shanks are particularly convenient for quick-change systems and impact drivers.
- Set Size and Range: Consider the variety of bit sizes included in a set. A comprehensive set ensures you have the right diameter for different tasks, while duplicates of frequently used smaller sizes can be a lifesaver.
- Brand Reputation: Reputable brands like DEWALT, Bosch, and toolant often invest in superior materials and manufacturing processes, leading to more consistent quality and performance.
Budget Planning
Drill bits for steel vary significantly in price, depending on their material, coating, and brand. Basic HSS sets are the most affordable but will struggle with hardened or stainless steel. Cobalt bits (M35 or M42) represent a mid-to-high price range but offer a far better return on investment due to their durability and efficiency in tough materials. Bits with advanced coatings like TiAlN will be at the higher end. When budgeting, consider the frequency and intensity of your steel drilling tasks. Investing in a higher-quality cobalt set can save you money in the long run by reducing bit replacement frequency and preventing project delays.
Final Thoughts
Choosing the right drill bits for steel is about matching the tool to the task. For general use with mild steel, a good quality TiN-coated HSS set might suffice. However, for consistent work with stainless steel, hardened steel, or cast iron, cobalt (M35 or M42) bits are indispensable. Always prioritize bits with a 135-degree split point and consider features like a three-flat or hex shank for improved grip. Proper technique, including using appropriate speed and cutting fluid, will also significantly extend the life of your drill bits, regardless of their quality.
Frequently Asked Questions
Q: What type of drill bit is best for drilling hardened steel?
A: For hardened steel, M35 or M42 cobalt drill bits are highly recommended. The cobalt alloy content provides superior heat resistance and hardness, allowing them to maintain their cutting edge at the high temperatures generated when drilling very hard materials. Bits with Titanium Aluminum Nitride (TiAlN) coatings further enhance this performance.
Q: Can I use regular HSS drill bits on stainless steel?
A: While you might be able to make a shallow mark, regular HSS (High-Speed Steel) drill bits are generally not recommended for drilling stainless steel. Stainless steel is much harder and generates more heat, which will quickly dull and destroy standard HSS bits. Cobalt drill bits (M35 or M42) are the best choice for stainless steel due to their ability to withstand high heat and maintain sharpness.
Q: What is the benefit of a 135-degree split-point tip?
A: A 135-degree split-point tip offers several benefits when drilling hard metals like steel. It is self-centering, meaning it starts drilling on contact without “walking” across the surface, eliminating the need for a pilot hole or center punch in many cases. It also requires less thrust force and breaks chips more efficiently, which reduces heat and improves drilling speed and accuracy.
Q: Do I need to use cutting fluid when drilling steel?
A: Yes, it is highly recommended to use cutting fluid or coolant when drilling steel, especially stainless and hardened varieties. Cutting fluid helps to dissipate heat, lubricate the cutting edge, and flush away chips. This significantly extends the life of your drill bit, improves cutting efficiency, and produces a cleaner hole. Without it, bits can quickly overheat, dull, and fail.
Q: Why do my drill bits keep breaking when drilling steel?
A: Drill bits breaking when drilling steel can be due to several factors: using the wrong type of bit (e.g., HSS instead of cobalt), excessive feed pressure, insufficient cutting speed, lack of coolant, or allowing the bit to overheat. Ensure you’re using a quality cobalt bit, applying steady, moderate pressure, using a slow drill speed, and constantly applying cutting fluid to prevent overheating and premature wear or breakage.
Selecting the best bits for drilling steel is essential for anyone tackling metalworking projects. From the exceptional durability of DEWALT’s titanium nitride coated bits to the specialized strength of toolant’s TiAlN-coated cobalt and the robust value of M35 cobalt options, there’s a perfect bit set for every need and budget. Remember to consider the material, coating, and point angle when making your choice, and always prioritize proper drilling techniques to maximize bit life and achieve professional results. Don’t let tough steel slow you down – invest in a quality set today and drill with confidence!
I’m Darrell Julian, the founder, lead writer, and hands-on welding enthusiast behind ArcWeldingPro.com. With more than 15 years of real-world welding experience, I created this platform to share what I’ve learned in the field, in the shop, and in the heat of the arc.
