The world's most in-depth and scientific reviews of tech gear

How We Tested Cordless Drills

Thursday May 23, 2019

To test out cordless drills and see which one is really the best you can get, we started off by comparing and researching all the most popular and promising tools, then bought all the top drills to test head-to-head. We drilled hundreds and hundreds of holes, drove screw after screw, and pushed these products to the limits with some ridiculously large hole saws, along with a handful of other tests. We divided our tests into four different groups, each weighted proportional to their significance, with a full description of our testing procedures and processes below.

We drilled through a 16 gauge steel sheet.
We drilled through a 16 gauge steel sheet.

Drilling


An obvious choice when evaluating the performance of cordless drills, our first metric assessed and scored how well each tool did at drilling holes in a variety of different materials, which accounts for 35% of the score for each drill. Starting off, we used a 1" paddle bit in each drill to drill several holes with each drill in a standard 2x12 that we got from our local home center.

Lag screws proved to be a tough challenge.
Lag screws proved to be a tough challenge.

We scored each drill based on how much it struggled, if it overheated, and if we needed to downshift into the slower gear to successfully drill through the board. This proved to be too much for some of the weaker drills, so we docked them points and tried again with a ½" twist drill.

Next, we moved on to seeing how well each drill did at drilling through metal. We stacked up two thinner sheets of metal to make the equivalent of a 16 ga. sheet, clamped it to the top of a board, and then used each tool to drill a ¼" and ½" hole in it with a normal twist drill.

We used multiple twist bits to keep the drills on a level playing field.
We used multiple twist bits to keep the drills on a level playing field.

We scored each drill on how long it took to get through the metal and how much each one struggled.

Our final drilling test was a true torture test for these products. We attempted to drill through a solid core door with a 5" diameter hole saw, something much more difficult than anything most people will ever use a handheld cordless drill for.

The Porter Cable didn't take long to devour the 5" hole saw test.
The Porter Cable didn't take long to devour the 5" hole saw test.

We again awarded points based on how long it took and how much each drill struggled, deducting points if any overheated and stopped working. We also deducted points if any started smoking, which a few of the cheaper drills did.

The DEWALT DCD710S2 (12-volt) hard at work driving in a lag screw.
The DEWALT DCD710S2 (12-volt) hard at work driving in a lag screw.

Driving


Next, we looked at the second most common use for these products: driving in screws and other fasteners. This metric is comprised of two tests and also accounts for 35% of the score for each drill.

Starting off, we drove in dozens and dozens of wood screws to two stacked 2x12's, noting how fast each drill could drive the screws, if they struggled at all, and if they could drive them to their full depth — flush with the surface.

Trying to get the optimal spacing for our driving test.
Trying to get the optimal spacing for our driving test.

We didn't pre-drill the screws, but we did get them started by using a cheap screwdriver as a punch to create a divot in the wood. We also used star drive screws, to ensure that the bits never slipped in this test.

Next, we upped the ante for these tools and moved on to driving in some 5" long. ½" lag bolts to connect a 2x4 to a 4x4. We predrilled the boards with the appropriate size pilot holes (5/16") and then used an adapter with a socket to drive them in.

We predrilled holes for the lag screws.
We predrilled holes for the lag screws.
We gave the top marks to tools that drove the lag screws to their full depth without struggling and deducted points from models that stalled out part way through or struggled to drive them in.

Many drills and many chargers.
Many drills and many chargers.

Included Battery


Following our drilling and driving metrics, we moved on to rating and scoring the included batteries with each drill. This accounts for 20% of the overall score for each tool and is based on how long each battery lasts, how long they took to charge, and the number of batteries included. We used whatever battery size came standard with each drill, so some models were at a slight disadvantage in the battery life test, but they did charge much faster.

To determine how long each of these batteries lasted, we charged each one up completely, then alternated drilling three 1" holes and driving in 16 screws in 2x12's until the battery died.

Test boards partway through battery testing.
Test boards partway through battery testing.

We then timed how long it took each battery to recharge, awarding the most points to the models that charged the fastest.

Some drills came with more than one battery.
Some drills came with more than one battery.

Finally, we compared the number of batteries included with each drill and awarded points accordingly.

The tabs on the PS31's battery can be a little finicky increasing their difficulty to be removed.
The tabs on the PS31's battery can be a little finicky increasing their difficulty to be removed.

Convenience


For the last 10% of the final score, we looked at how convenient and easy to operate each drill is. These products are all roughly the same, but there are a few features that make some models much more enjoyable to use.

The most important things we compared in this metric is how much each drill weighed and if it has a belt clip. While even the heaviest of these products might not seem that heavy at first, but you will definitely start to feel weighed down by the heavier ones after a full day of driving screws and drilling holes. We also found a belt clip to be invaluable, as it makes it infinitely more convenient to clip the drill to your belt rather than setting it down every time — especially when working on a ladder or step stool.

We also compared how well the integrated LEDs lit up your work area and the difficulty of swapping batteries and the ease of using the locking mechanism.

Good light from a drill makes lining up the bit easier.
Good light from a drill makes lining up the bit easier.

We also awarded points if the drills had a battery indicator and if you have different gear modes to adjust the speed and torque. Finally, we also compared and scored each drill on their chuck's range of adjustability.

Conclusion


Hopefully, this has provided you with some background information about how we tested and scored these and why you can trust our recommendations next time you are shopping for a new cordless drill.