What Size is a Number 7 Drill Bit? [A Simple Guide]

Drill bit sizes are numbered from 80 to 1, with 80 being the smallest and 1 being the biggest. As a result, drill bit #7 is on the bigger side of your typical drill set.

However, the question is, what exactly is the size of a #7 drill bit?

The size of a drill bit corresponds to the breadth or thickness of its substructure. A specific task will require a certain or precise bit size.

For this reason, it is essential to get familiar with the various sizes to understand their use.

What Is A Number 7 Drill Bit?

The size of a number 7 drill bit is 0.2010 inches. The decimal 0.2010 is 201/1000 as a fraction.

Standard fractional drill bits, on the other hand, come in 1/64-inch sizes. As a result, there are no standard fractional drill bits, exactly 201/1000 as the #7 drill bits.

On the other hand, to get the closest gauge wire #7 drill bit equivalent in fractional inches, round 201/1000 up to and down to 1/64 accuracy.

Because of rounding, a 3/16 drill bit creates a smaller hole than a #7 drill bit, and a 13/64 drill bit makes a larger hole than a #7 drill bit.

This article will help you get familiar with the #7 drill bit measurements and many more. Also, this will discuss determining the drill bits sizes that will suit your task.

Keep reading to discover the best drill bit for your job.

What Do the Numbers Represent on a Drill Bit?

Drill bits come in fractional, metric, wire gauge numbers, and letter sizes. Metric measures are measured in millimeters, whereas fractional measurements are measured in inches.

The letter and wire gauge systems correlate to tool sizes that rise from #107 to #1 and then from A to Z as the wire gauge lowers. The dimensions’ decimal equivalents are in both English and Metric units.

The drill standard specifies sizes ranging from 1 to 97. In reality, number sizes larger than #80 are uncommon.

Number and letter sizes are widely used in the United States and, to a lesser degree, the United Kingdom, but are no longer used in the majority of the world, which has become entirely metric.

Drill Bit Sizes

Drill bits are available in a wide range of standard sizes. It is critical to verify that the bit size you want to use is suitable for your drill.

It should fit precisely into the chuck (the gripping clamp) for a tight fit that will resist the drilling pressure.

9.53mm and 12.7mm are two of the most popular drill bit sizes. In contrast, the smallest sizes available in drill bit sets may vary from 0.3mm to 16mm, with maximum sizes ranging from 1.6mm to 80mm.

How to Choose the Correct Drill Bit Size for a Screw

Choosing a drill bit may seem to be a minor aspect of the construction process, but it has the potential to alter everything radically.

Fortunately, there are many techniques you can use to verify that you’re selecting the correct screw sizes. All you need to do is follow the instructions below:

Option 1:

Take the screw you’re using and the drill bit that seems to be the closest size. When lining them up end to end, make sure the drill bit is the same width as the screw without the threads.

If that’s the case, you’re good to go.

Option 2:

Locate the labels on each box of screws and pieces. The dimensions of almost all drill bits are indicated on the bit itself.

You’ll need to locate the box or bag that the screws arrived in. Use a 1/16 bit for a number 2 screw.

Use a 9/64 bit for a number 9 screw. If you get lost, look up graphs and refer to the packing.

Option 3:

You should reverse the second option if you’re using washers and other materials that sometimes need a loose screw.  

Line up the screw and drill the bit from end to end, ensuring the bit is the same width as the screw with threads. This prevents the screw from sealing too tightly against the surface, enabling you to utilize a washer.

FAQ

How Are Drill Bits Measured?

Drill bits often include marks on the shank above the threads. It’s tiny, but the drill-bit diameter is typically stamped into the metal.

The number marks are usually written infractions. For instance, the marks might be 1/4-inch, 3/6-inch, or 25/32.

However, if you cannot find any number markings on the drill bit, you can use a drill bit gauge.

A drill bit gauge can be used to measure brad point bits, twist drill bits, or any other kind of straight drill bit. Starting at 1/16″, the gauge can measure up to 1/2″ in 1/64th-inch increments.

How Do You Put a Small Drill Bit in a Drill?

Smaller drill bits, such as 1/8th-inch drill bits, may be challenging to put into the chuck of many drills.

They may slide during usage if not securely fastened. It is usually advisable to check the instructions since, in certain instances, inserting by hand rather than using the motor may be a better option.

When using, do not push too hard and let the drill perform the heavy job of cutting.

Should A Drill Bit Be The Same Size As The Screw?

The job at hand determines the answer. Your drill bit should be the same width as the screw without the threads most of the time.

However, your intended task usually determines the exact drill bit sizes for screws. Here are some things to think about when choosing a drill bit size for your screw:

1. Size of the tap. The smaller than the outer thread size but slightly larger than the internal thread size allows running a tap through it to form the threads and engage them.
2. Dimensions of clearance. It should be larger enough to pass the threads and shank easily.
3. Loose clearance size. It allows for delayed fitting of loose tolerance objects but prevents the head from passing through.

How to Choose a Drill Bit By Type?

Drill bits are classified by their types designated for wood, masonry, metal, and many more. Here are the types of drill bits and their uses:

Twist Drill Bits

Twist bits are perhaps the most popular drilling equipment used by the average handyman using a manual or power drill.

The front edges cut the material, while the spirals down the length remove debris from the hole while keeping the bit straight.

They are suitable for use on wood, metal, plastics, and other comparable materials. The majority of twist bits are composed of one of two materials:

1. ‘High-speed steel’ (HSS)is ideal for drilling most materials. While drilling metal, the HSS can withstand high temperatures.
2. ‘Carbon Steel’s specifically ground for drilling wood and should not be used for drilling metals. They are brittler and less malleable than HSS pieces.

Screwdriver Drill Bits

These bits feature a hexagonal shank and are designed to fit in rechargeable screwdrivers. They are excellent for drilling pilot holes, but their use is restricted due to the low power of these screwdrivers and the limited size of tiny bits available.

Masonry Bits

Masonry bits are intended for drilling into brick, block, stone, quarry tiles, or concrete. The cutting tip is often composed of tungsten carbide that has been bonded to a spiral steel shaft.

Some masonry drills are called ‘durum tipped,’ which refers to a durable silicon bronze alloy used as the cutting point instead of tungsten.

Spur Point Bits

They feature a central point and two elevated spurs that assist keep the bit drilling straight. They are also known as wood or dowel bits.

When used in a power drill, the bit slices wood quickly and leaves a clean-sided hole.

Because the sidewalls of the holes are clean and parallel, they are excellent for drilling holes for dowels. Spur point bits should only be used to drill wood and specific polymers.

Pilot Bullet Point

Bullet drills feature a central point and two spurs, similar to spur point bits, but they may be used in metal, wood, and plastics.

Unlike standard twist drills, the twisted flutes are ground away, resulting in a more accurate bit. When they break through the rear of the workpiece, they cut a clean hole and do minimal harm.

Countersink

Although not an actual ‘drill,’ it is used in a power or manual drill to create the conical recess for countersunk screw heads. These bits are often intended for use on soft materials such as wood and plastics rather than metals.

Tile Bits

These bits have a ground tungsten carbide tip and are used to drill ceramic tiles and glass. They may be used with a hand drill, but they work best with a variable speed power drill set at slow.

Flat Wood Bits

The flat wood bit is solely designed for use with a power drill; the center point locates the bit, and the flat steel on each side slices away the lumber.

These bits are used to drill fairly big holes and provide a flat-bottomed bore, making them suitable for wood recessed screw/bolt heads.

To bore deep holes, the bigger bits need the use of a power drill. Flatwood bits aren’t ideal for expanding an existing hole.

Hole Saw Bits

A hole saw is a tool used to cut large, fixed-diameter holes in wood or plastic. They typically cut to a depth of 18mm or deeper. The blade saws its way through the material, and it is best utilized in a power drill at moderate speed.

Forstner Bits

These bits are used to create holes with a flat bottom, such as those used for kitchen cabinet hinges. Because there is little in the way of a central point, it is best utilized in a power drill placed in a drill stand.

Wood Auger

When drilling large-diameter, deep holes in wood, or strong artificial boards, this is perfect. In most cases, an Auger bit should only be used in a hand brace.

The bit will create clean, deep holes with a flat bottom. The single spur defines and cuts the hole’s edge, while the chisel-like cutting edge eliminates waste inside the already-cut circle.

What Are Numbered Drill Bits Used For?

Drill bits with numbers were created to bridge the gap between metric and fractional sizes. The most frequent use is for utilizing taps.

There will not be an exact match for fractional sizes, but you may refer them to the next fractional bit bigger than the numbered bit.

Now You Know #7 Drill Bit

Choosing the right size drill bit makes a significant impact. As a result, it is important to familiarize yourself with the facts stated above, like the size of a #7 drill bit.

Remember that the #7 drill bit has a size of 0.2010 inches, which is also equivalent to 3/16 and 13/64 in fractional measurement.

You can properly select the appropriate size for your work by following this information and the instructions highlighted in the article.