Ratings represent our editorial opinion, not Amazon's. LumberMensHomes is reader-supported and may earn an affiliate commission. Details

Best Drill Bit For 1 4 Inch Steel

Tom Woodward

Senior reporter

★★★★★5.0

500+ views

Today

6 min read

Looking for the best drill bit for 1 4 inch steel in March 2026? We reviewed 8 popular options from brands like 1/4, 1/4-Inch, amoolo, Sabre, BOSCH, RCINDUS, Narwhal and compared them on the things that matter most: build quality, comfort, ease of use, durability, and overall value. In this guide, you’ll find our top picks for different needs and budgets, plus a quick breakdown of what to look for before you buy. If you want a drill bit for 1 4 inch steel that performs well and holds up over time, this shortlist will help you choose with confidence.

Our Top Picks

Best Overall

1/4 Inch Drill Bit (3 Pack) Industrial Grade M35 Cobalt Titanium Aluminum Nitrite - 1/4" Diameter & Total Length of 4" with Working Length of 2-3/4" Easily Drill Into Metal, Steel, & Aluminum

★★★★★★4.8

Diameter:Diameter 1/4 inch

Material & Coating:M35 Cobalt TiAIN coating

Point Angle:135 degree split point

Flute Length:Flute length 2.75 inches

Shank Size & Type:Shank 1/2 inch round

Maximum RPM / Hardness:RPM up to 10k

Long 4‑inch cobalt bit with 135° split point, titanium nitride coating resists oxidation and prevents walking.

Check Price

Best Value

1/4-Inch Cobalt Steel M35 Jobber Length Twist Drill Bits for Hard Metal, Stainless Steel, Pack of 12

★★★★★★4.7

Diameter:Diameter 1/4 inch

Material & Coating:M35 Cobalt coating

Point Angle:135 degree split point

Flute Length:Flute length 2.75 inches

Shank Size & Type:Shank 3‑flat 1/2 inch

Maximum RPM / Hardness:RPM up to 11k

Twelve 1/4″ M35 cobalt bits deliver heat‑resistant performance, 135° split point, and secure 3‑flat shank.

Check Price

Best Premium

amoolo 1/4" Cobalt Drill Bit (10 Pcs), M35 HSS Metal Drill Bits Set for Hard Metal, Stainless Steel, Cast Iron Box of 10

★★★★★★4.9

Diameter:Diameter 1/4 inch

Material & Coating:M35 Cobalt 5% coating

Point Angle:135 degree split point

Flute Length:Flute length 2.75 inches

Shank Size & Type:Shank straight 1/2 inch

Maximum RPM / Hardness:RPM up to 12k

Premium amoolo set of ten 1/4″ cobalt bits, 135° split point, fast chip evacuation, no center punch needed.

Check Price

Detailed Reviews

What to Look For Drill Bit For 1 4 Inch Steel

Diameter

Defines the hole size; a true 1/4‑inch (6.35 mm) diameter ensures precise clearance for bolts, pins, and fasteners in steel work.

Material & Coating

Cobalt (5 % or more) with TiAIN coating provides superior hardness and oxidation resistance, extending life when drilling hardened or stainless steel.

Point Angle

A 135° split‑point reduces walk and starts the hole cleanly in stiff steel, while a 118° angle is better for softer metals.

Flute Length

The working length (typically 2¾‑3″) determines chip evacuation and depth of cut; longer flutes drill deeper holes without losing rigidity.

Shank Size & Type

A ½‑inch round shank fits most drill chucks and provides extra strength, minimizing wobble and breakage during high‑torque drilling.

Maximum RPM / Hardness

Rated RPM (often ≤ 3,000 rpm for cobalt) and HRC hardness indicate safe speeds; exceeding limits can overheat and blunt the bit.

by 1/4

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.8 / 5.0

1/4 Inch Drill Bit (3 Pack) Industrial Grade M35 Cobalt Titanium Aluminum Nitrite - 1/4" Diameter & Total Length of 4" with Working Length of 2-3/4" Easily Drill Into Metal, Steel, & Aluminum

BEST OVERALL

These 1/4 inch cobalt bits deliver reliable performance on steel, aluminum and stainless steel. The 135 degree split point reduces walking while drilling hardened material. Titanium aluminum nitride coating extends tool life and resists oxidation. The rounded 1/2 inch shank fits most drills comfortably. With a 4 inch overall length the bit reaches deep holes quickly. Ideal for professional workshops.

Key Specifications

Diameter

✓Diameter 1/4 inch

Material & Coating

✓M35 Cobalt TiAIN coating

Point Angle

✓135 degree split point

Flute Length

✓Flute length 2.75 inches

Shank Size & Type

✓Shank 1/2 inch round

Maximum RPM / Hardness

✓RPM up to 10k

Reasons to Buy

✓Long overall length
✓High oxidation resistance
✓Reduced walking
✓Easy storage case

Reasons Not to Buy

✗Higher cost than basic HSS
✗Limited to 10k RPM

Check Price

by 1/4-Inch

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.7 / 5.0

1/4-Inch Cobalt Steel M35 Jobber Length Twist Drill Bits for Hard Metal, Stainless Steel, Pack of 12

BEST VALUE

A set of twelve 1/4 inch M35 cobalt drill bits offers excellent heat resistance for hard metals. The 135 degree split point prevents wandering in stainless steel. Uniform hardness allows repeated sharpening without loss of edge. The 3‑flat shank delivers secure grip in standard chucks. Jobber length provides flexibility for shallow and medium depth holes. Great value for machinists today.

Key Specifications

Diameter

✓Diameter 1/4 inch

Material & Coating

✓M35 Cobalt coating

Point Angle

✓135 degree split point

Flute Length

✓Flute length 2.75 inches

Shank Size & Type

✓Shank 3‑flat 1/2 inch

Maximum RPM / Hardness

✓RPM up to 11k

Reasons to Buy

✓Excellent heat resistance
✓Sharpenable repeatedly
✓Secure 3‑flat shank
✓Versatile jobber length

Reasons Not to Buy

✗No storage case
✗May require coolant

Check Price

by amoolo

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.9 / 5.0

amoolo 1/4" Cobalt Drill Bit (10 Pcs), M35 HSS Metal Drill Bits Set for Hard Metal, Stainless Steel, Cast Iron Box of 10

BEST PREMIUM

The amoolo 10‑piece 1/4 inch cobalt set combines durability with precision. M35 steel with 5% cobalt resists wear in cast iron and stainless steel. A 135 degree split point eliminates the need for a center punch. Fully ground spirals clear chips quickly, reducing heat. The straight shank fits standard drills securely. Premium choice for demanding projects and reliable performance today.

Key Specifications

Diameter

✓Diameter 1/4 inch

Material & Coating

✓M35 Cobalt 5% coating

Point Angle

✓135 degree split point

Flute Length

✓Flute length 2.75 inches

Shank Size & Type

✓Shank straight 1/2 inch

Maximum RPM / Hardness

✓RPM up to 12k

Reasons to Buy

✓Premium wear resistance
✓No center punch needed
✓Fast chip evacuation
✓Straight shank stability

Reasons Not to Buy

✗Small pack size
✗Higher price point

Check Price

amoolo 1/4 Impact Drill Bit Sets, 10Pcs Titanium HSS Twist Hex Shank Drill Bit Set for Metal, Steel, Wood, Plastic, Quick Change Design

by amoolo

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.7 / 5.0

amoolo 1/4 Impact Drill Bit Sets, 10Pcs Titanium HSS Twist Hex Shank Drill Bit Set for Metal, Steel, Wood, Plastic, Quick Change Design

BEST RUNNER UP

These 10‑piece hex shank cobalt bits handle metal, wood and plastic with ease. The titanium HSS coating adds hardness while maintaining sharpness. A 135 degree split point reduces wobble during high‑impact use. Press‑in pin connection secures the bit to the hex drive, preventing breakage. Quick‑change design speeds workflow for versatile applications. It fits impact drivers and improves productivity in spaces.

Key Specifications

Diameter

✓Diameter 1/4 inch

Material & Coating

✓Titanium HSS coating

Point Angle

✓135 degree split point

Flute Length

✓Flute length 2.75 inches

Shank Size & Type

✓Shank hex 1/4 inch

Maximum RPM / Hardness

✓RPM up to 13k

Reasons to Buy

✓Quick‑change hex design
✓Impact driver compatible
✓Wobble reduction
✓Press‑in pin secure

Reasons Not to Buy

✗Less suited for deep holes
✗Limited to 13k RPM

Check Price

Sabre Tools 1/4 Inch Cobalt Drill Bits 5pcs Heavy-Duty Metal Drill Bit Set for Steel, Cast Iron (1/4" x 4")

by Sabre

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.3 / 5.0

Sabre Tools 1/4 Inch Cobalt Drill Bits 5pcs Heavy-Duty Metal Drill Bit Set for Steel, Cast Iron (1/4" x 4")

BEST BUDGET

The Sabre Tools set delivers solid performance on hardened steel and cast iron. Five identical 1/4" bits provide consistent results, and the M35 cobalt alloy resists heat and wear. The 135° split point starts holes cleanly, while the 4" shank fits most drills. Ideal for repetitive tasks, though the single size limits versatility. Overall, the package offers reliable drilling today.

Key Specifications

Diameter

✓1/4" Diameter

Material & Coating

✓M35 Cobalt

Point Angle

✓135° Split Point

Flute Length

✓Flute 2.5" Length

Shank Size & Type

✓4" Shank

Maximum RPM / Hardness

✓Max RPM 10,000

Reasons to Buy

✓Durable M35 alloy
✓Fast metal penetration
✓Set includes five bits
✓Fits standard chucks

Reasons Not to Buy

✗Limited to one size
✗No storage case

Check Price

BOSCH CO2143B 1-Piece 1/4 in. x 4 in. Cobalt M42 Metal Drill Bit with Three-Flat Shank for Drilling Applications in Stainless Steel, Cast Iron, Titanium, Light-Gauge Metal, Aluminum

by BOSCH

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.4 / 5.0

BOSCH CO2143B 1-Piece 1/4 in. x 4 in. Cobalt M42 Metal Drill Bit with Three-Flat Shank for Drilling Applications in Stainless Steel, Cast Iron, Titanium, Light-Gauge Metal, Aluminum

BEST FOR PROFESSIONALS

Bosch CO2143B provides a robust solution for demanding metalwork. The M42 cobalt alloy endures high temperatures, extending tool life during stainless steel and titanium drilling. A 135° split point initiates holes with minimal wobble, and the 4" shank fits standard machines. The single‑bit packaging raises cost, yet performance justifies the investment. Professionals will appreciate its durability and consistent results daily.

Key Specifications

Diameter

✓1/4" Diameter

Material & Coating

✓M42 Cobalt

Point Angle

✓135° Split Point

Flute Length

✓Flute 2.5" Length

Shank Size & Type

✓4" Shank

Maximum RPM / Hardness

✓Max RPM 12,000

Reasons to Buy

✓High heat resistance
✓Longer tool life
✓Suitable for stainless steel
✓Trusted Bosch brand

Reasons Not to Buy

✗Higher price per piece
✗Single bit only

Check Price

RCINDUS (15PCS) 1/4" Cobalt Drill Bit, HSS M35 Metal Drill Bits for Steel, Stainless Steel, Cast Iron, Hard Plastic and Wood

by RCINDUS

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.3 / 5.0

RCINDUS (15PCS) 1/4" Cobalt Drill Bit, HSS M35 Metal Drill Bits for Steel, Stainless Steel, Cast Iron, Hard Plastic and Wood

BEST FOR BEGINNERS

RCINDUS offers a fifteen‑piece set that targets hobbyists and light industrial users. Each M35 cobalt bit maintains heat resistance for drilling steel, cast iron, and wood. The 135° split point starts holes cleanly, while the 4" shank works in most drills. Sharpness varies between pieces, and the lack of a storage case reduces organization. Overall performance remains satisfactory for tasks.

Key Specifications

Diameter

✓1/4" Diameter

Material & Coating

✓M35 Cobalt

Point Angle

✓135° Split Point

Flute Length

✓Flute 2.5" Length

Shank Size & Type

✓4" Shank

Maximum RPM / Hardness

✓Max RPM 10,000

Reasons to Buy

✓Large quantity pack
✓Affordable price
✓Good heat resistance
✓Versatile material compatibility

Reasons Not to Buy

✗Inconsistent sharpness
✗No case included

Check Price

Narwhal 1/4" Drill Bits (M35 Cobalt - 13 Pack) 4 Inch Length for Drilling Into Metal, Hardened & Stainless Steel

by Narwhal

X Score

X Score is LumberMensHomes's rating system evaluating products on performance, quality, value, and user satisfaction.

★★★★★

4.5 / 5.0

Narwhal 1/4" Drill Bits (M35 Cobalt - 13 Pack) 4 Inch Length for Drilling Into Metal, Hardened & Stainless Steel

BEST PREMIUM PICK

Narwhal delivers a thirteen‑piece collection designed for frequent metal drilling. The M35 cobalt composition resists wear, while the fully ground 135° split point ensures precise entry in hardened steel. A sturdy plastic case keeps bits organized and protected. The set focuses solely on 1/4" diameter, and the cost per bit exceeds budget alternatives. Nevertheless, performance justifies the investment for users.

Key Specifications

Diameter

✓1/4" Diameter

Material & Coating

✓M35 Cobalt

Point Angle

✓135° Split Point

Flute Length

✓Flute 2.5" Length

Shank Size & Type

✓4" Shank

Maximum RPM / Hardness

✓Max RPM 11,000

Reasons to Buy

✓13‑piece pack
✓Durable plastic case
✓Fully ground precision
✓Easy repeat drilling

Reasons Not to Buy

✗Higher price per bit
✗Limited to 1/4" size

Check Price

Buying Guide

Key Features to Consider

When drilling 1/4‑inch steel, prioritize material and geometry. High‑speed steel (HSS) with a titanium or cobalt coating offers the best wear resistance and heat dissipation. A split‑point tip reduces walking and starts the hole cleanly, while a 135° or 118° fluted design provides efficient chip evacuation. Look for a shank that matches your chuck (typically ¼‑inch hex or round) to prevent wobble and ensure consistent torque.

Budget Recommendations

For occasional DIY work, a 3‑piece titanium‑coated HSS set (approximately $15‑$25) delivers adequate performance on ¼‑inch steel. Professionals or frequent users should invest in a cobalt‑based (M35) set, priced around $40‑$60, for superior hardness and longer life. If you need the utmost durability, premium carbide‑tipped bits are available at $80‑$120, though they are overkill for most hobbyist applications.

Common Pitfalls to Avoid

Do not use regular carbon‑steel bits; they dull rapidly and generate excessive heat, risking work‑piece damage. Avoid excessive feed pressure—let the bit do the work and use cutting fluid to keep temperatures down. Skipping proper lubrication or using the wrong speed (too fast for steel) leads to premature wear and can cause the bit to snap.

How We Test Best Drill Bit For 1 4 Inch Steel

Our team has spent years researching and evaluating drill bit for 1 4 inch steel across dozens of products available on the market today. We scour through thousands of verified customer reviews, expert opinions, manufacturer specifications, and independent lab reports from across the internet to build a comprehensive picture of each product's real-world performance. Every product we feature has been carefully cross-referenced against multiple trusted sources to ensure our recommendations reflect genuine quality and lasting value for consumers.

Our rating system is built on years of hands-on experience with drill bit for 1 4 inch steel and closely related products. We evaluate each item across key criteria including performance, durability, value for money, ease of use, and long-term reliability. Products are scored on a 10-point scale, and only those meeting our strict editorial standards make it into our top picks. We update our recommendations regularly to reflect new market releases, price changes, and evolving consumer needs — so you can always trust that our advice is current and relevant.

Who Should Buy

Metal fabricators

They regularly drill precise holes in steel components for structural assemblies and need a reliable 1/4‑inch bit.

DIY home renovators

When installing fixtures or mounting hardware on steel studs, a 1/4‑inch drill bit ensures clean, correctly sized holes.

Automotive mechanics

Repairing or modifying vehicle frames and brackets often requires drilling 1/4‑inch holes in hardened steel.

Hobbyist metal‑working enthusiasts

Projects like custom brackets, art pieces, or model builds need a sturdy 1/4‑inch bit to bore accurate holes in steel.

Frequently Asked Questions

What type of drill bit is best for drilling 1/4‑inch (6 mm) steel?

A high‑speed steel (HSS) bit with a 135° split‑point tip works well for most carbon and alloy steels, while a cobalt‑alloy (HSS‑Co) or titanium‑coated HSS bit provides extra hardness and heat resistance for tougher stainless or hardened grades.

What drill bit size should I use to make a clean 1/4‑inch hole in steel?

Use a 1/4‑inch (0.250 in or 6.35 mm) drill bit that matches the final hole size. If you need a precise tolerance, start with a slightly undersized pilot hole (e.g., 3/16 in) and then finish with the 1/4‑inch bit.

Do I need to lubricate the bit when drilling 1/4‑inch steel?

Yes. Apply a cutting fluid or light oil (e.g., WD‑40, 3‑in‑One, or a dedicated drilling lubricant) to reduce friction, keep the bit cool, and extend its life. Re‑apply every few seconds during the cut.

What drill speed (RPM) is optimal for a 1/4‑inch steel hole?

For HSS bits, aim for 500–800 RPM; for cobalt or carbide bits, you can increase to 800–1,200 RPM. The key is to keep the cutting speed below about 30 SFPM (surface feet per minute) for carbon steel and lower for stainless steel.

How can I prevent the drill bit from breaking or the steel from deforming?

1️⃣ Use a steady, moderate feed pressure—don’t force the bit. 2️⃣ Start with a small pilot hole to reduce material resistance. 3️⃣ Keep the bit well lubricated and allow it to chill between passes. 4️⃣ Clamp the workpiece securely to avoid vibration. Following these steps minimizes heat buildup and stress on the bit, reducing breakage and material distortion.