What Do the Numbers on a Drill Mean?

If you have ever picked up a cordless drill and wondered what the numbers around the collar are for, you are not alone. It is one of the most common questions I get from customers, and the answer will save you from snapped screw heads and ruined plasterboard.

I use two DeWalt drills every day in my handyman work and around my own home: the DCD778 and the DCD776. They are very similar in layout, so everything below applies to both, and to most other cordless drills too.

The reason I have two is simple. One is set up for pilot holes with a drill bit, with the collar set to the drill symbol. The other is used for driving screws, with the clutch set to the correct number for the job. It saves me swapping bits and changing settings back and forth, and it means I never drive a screw on the drill setting, which gives no clutch protection and is how screw heads get snapped or sunk too deep.

I also have an impact driver, but I use it mainly for driving a high volume of screws where a precise finish is not needed. If you are not sure what sets it apart from a drill, I explain what an impact driver is used for in a separate guide. For anything that does need a neat, controlled finish, I stick with the combi drill and its clutch.

The Numbers on the Collar are Torque Settings

The ring behind the chuck, with the numbers running from 1 up to 15, is the clutch. It controls how much twisting force (torque) the drill delivers before it stops driving and clicks.

• Low numbers (1 to 5): very little torque. Use these for small screws, delicate fittings and soft materials.
• Middle numbers (6 to 10): a good general range for everyday screwdriving.
• High numbers (11 to 15): more torque for larger screws into dense material like hardwood.

The clutch is there so you do not overdrive a screw. Once the screw is seated and the resistance reaches your chosen setting, the clutch slips with a ratcheting click instead of burying the head or stripping the thread. If the drill clicks before the screw is fully in, turn the number up. If the screw head is sinking too far, turn it down.

My advice is to start low and work up. It takes a few seconds and costs you nothing.

Which Clutch Setting Should You Use? Examples From My Work

Here are the settings I reach for on real jobs. Treat them as a starting point, because the right number depends on your screw, the material and how charged the battery is. If the drill clicks before the screw is home, go up one or two numbers.

Job	Material and screw	Setting
Fitting cabinet door handles	Small machine screws into MDF or chipboard	3
Assembling flat-pack furniture	Chipboard with small fixings	4
Securing a wall mounting bracket to the back of a TV	Small TV M6 bolts	5
Fitting door hinges	25mm screws into a softwood frame	6
Installing plasterboard	12.5mm plasterboard with 38mm plasterboard screws	8
Fixing shelf brackets to a stud wall	40mm screws into timber studs	8
Fixing plywood sheets	18mm ply with 40mm screws	10
Securing pieces of softwood together	25mm softwood with 50mm woodscrews	12
Fitting decking boards	60mm decking screws into treated joists	14

A few tips from using these every day:

• Delicate jobs, low numbers. For flat-pack and small fixings, a low setting stops the screw head crushing the surface or stripping the thread.
• Plasterboard needs care. Setting 8 sinks the screw head just below the surface without tearing the paper face, which is what you want before filling and taping.
• Dense or long screws, high numbers. Decking and big structural screws need much more twisting force, so I move towards the top of the dial.
• Pilot holes still matter. Use the drill symbol (no clutch) for pilot holes, and the hammer symbol only for masonry. Then switch back to a number for driving the screw.

The Drill and Hammer Symbols

Beyond the numbers, you will see two symbols on the collar.

• Drill bit symbol: straight drilling with no clutch. The drill delivers full power, which is what you want for making holes in wood and metal.
• Hammer symbol: adds a rapid hammering action for drilling into brick, block and masonry. Both the DCD778 and DCD776 are combi drills, so they have this mode. You can read more about how hammer drills work on Wikipedia.

Never leave it on the hammer setting when drilling wood or screwing, as it will chew up the work. If you are still deciding which type of drill suits your jobs, my cordless combi drill and impact driver buying guide explains how to use each one and what to look for when buying.

The 1 and 2 on Top of the Drill

There is a second set of numbers on top of the body, usually just 1 and 2. This is the gear selector.

• 1: low speed with higher torque. Best for driving screws and drilling large holes.
• 2: high speed with lower torque. Best for drilling smaller holes quickly.

Only change gear when the drill has stopped, otherwise you risk damaging the gearbox.

Other Reasons You Might Strip a Screw Head

The clutch setting is only part of the story. Even with the right number selected, a screw head can still strip for other reasons. These are the four I see most often.

1. Poor quality screws

Cheap screws are often made from soft or poorly treated metal, so the recess deforms the moment you put load through it. I have also noticed that some low-cost imported screws do not play well with European drive bits. The recess can be shallow or badly formed, so the bit never seats properly and spins out. Buying decent screws from a reputable supplier costs a little more, but it saves a lot of frustration and ruined heads.

2. Using the wrong bit for the screw

This is the big one. Many people grab whichever bit is closest, but a bit that is nearly the right fit is the wrong fit. Know your screw head types:

• Pozidriv (PZ): the most common head on modern wood screws. It has a cross shape with small extra marks between the arms. The common sizes are PZ1, PZ2 and PZ3, with PZ4 used for larger fixings. PZ2 is the one I use most.
• Phillips (PH): a similar cross shape, but without the extra marks. A Phillips bit in a Pozidriv screw (or the other way round) will cam out and chew the head.
• Torx (TX): a six-pointed star shape that grips very well and is much harder to strip. Sizes are shown as T20, T25 and so on.
• Slotted: a single straight slot. Common on older fixings, but the bit slips off easily.
• Hex (Allen): a six-sided recess, used in bolts and some furniture fittings.
• Square (Robertson): a square recess, popular in some decking and construction screws.

The bit should sit snugly in the recess with no wobble. If it rattles around, try the next size down or check you have the right type. Slipping heads are very common when using the incorrect size driver head.

3. Not lining up the drill with the screw

The drill and bit need to be in a straight line with the screw, at 180 degrees or as close to it as you can get. If you drive at an angle, the bit rides up and out of the recess and takes the edges of the head with it. Keep the drill square to the work from the first turn to the last.

4. Applying the wrong amount of pressure

The pressure you put behind the drill matters as much as the clutch setting. If you do not push hard enough, the bit slips in the recess and the head strips. If you push too hard, you can force the screw too deep into the material and sink the head below the surface. You want firm, steady pressure that keeps the bit seated without leaning on the drill with all your weight.

5. Using too much power without the clutch

An overpowered drill on the drill symbol, with no clutch set, will keep turning long after the screw is home. That is how heads get snapped, sunk too deep or stripped. Use the clutch numbers covered earlier and you will stop the drill at the right moment instead of fighting it.

Other Numbers Worth Knowing

• 18V: the battery voltage. Both my drills are 18V XR, so the batteries swap between them.
• Ah (such as 2.0Ah or 5.0Ah): battery capacity. A higher number means longer run time.
• 13mm: the maximum chuck size, which is the largest drill bit shank it will hold.
• Nm: the maximum torque. The DCD778 is rated at 65Nm.

DCD778 vs DCD776

Having both gives me a good comparison. The DCD778 has a brushless motor, which runs more efficiently and is more compact. The DCD776 has a brushed motor. Both give you 15 torque settings, drill and hammer modes, and two speeds, so the numbers mean exactly the same on each. If you are weighing up brands as well, I compared them in my Milwaukee vs DeWalt tools guide.

Quick Summary

The numbers 1 to 15 are clutch torque settings, the symbols choose drilling or hammer mode, and the 1 and 2 on top are your speed gears. Get those three right, and you will drill and drive cleanly on every job.

To avoid stripped screw heads, match the clutch setting to the job, use the correct bit for the screw head, keep the drill lined up square with the screw, and buy decent quality screws. If you are tackling jobs around the house, my home maintenance checklist is a good place to put your drill to use.