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If you’re shopping online for Dewalt cordless power tools, you’ve most likely run across their 20v Max lineup. At first glance, the 20 volt power-tools and batteries might seem like the better buy. However, that being said, it’s not that cut-and-dry.

18 vs 20 volt

When looking at Dewalt tools and their competitors, you’ll see most comparable tools are 18 volts. Digging deeper into specific models, you may see that the 18 volt tools are similar in output to Dewalt’s 20 volt Max tools. So what’s really going on here?

Buried in the fine print, is a little sentence from Dewalt:

“Maximum initial battery voltage (measured without a workload) is 20, Nominal voltage is 18”

What the heck?

Lithium-ion batteries for power-tools are made up of cells wired in a series. When looking at an 18 volt battery, or even Dewalt’s 20v Max batteries, there are five cells per battery.

Each cell in the series of five, has a nominal voltage of 3.6 volts. Multiplied by five cells, this gives us our 18 volt total. From the manufacturer, each cell has a maximum voltage limit of four volts. So again, multiplying by five cells per battery, gives us 20v.

Dewalt isn’t being dishonest, they are just stretching the truth and using a bit of clever and deceptive marketing. They are advertising the maximum no-load voltage of twenty volts, however when the tool is being used in practical real-world scenarios, it’s actually an 18 volt tool.

It’s kind of like when a car manufacturer lists the horsepower of their vehicle. In the automotive industry, car manufacturers list the maximum peak engine output as the advertised horsepower. However in the real world, you won’t be using your car’s peak power all the time, the type of gasoline you use, the friction of internal parts, what elevation you are at, the size of your tires, how maintained or how old the car is, etc. all mean that the horsepower that connects the wheels to the road is much less than the advertised on-paper number.

Marketing gimmick?

Dewalt 20v Max lineup of power-tools are essentially the same as 18-volt power tools. The maximum 20v rating is of little practical worth. The tools do have a maximum voltage of twenty volts, but that’s only when they are sitting there, unused. When actually pulling the trigger, and applying a load to the power-head, the voltage drops to 18 volts.

It’s in the Details

It’s a bit misleading, but it is truthful. It’s important to look at the specifications of each individual model when comparing. It’s not always the case that a Dewalt 20v max power-tool is better than a competitor, like Bosch or Milwaukee. For instance, Milwaukee M18 lineup are 18 volt power-tools. When comparing the M18 cordless drill to a Dewalt 20v Max drill, take a look at the maximum rpm of each. The Dewalt drill has a 450/1500 rpm maximum – for low and high speed setting. The Milwaukee M18 drill has a 500/1800 rpm rating. The Milwaukee M18 drill also has more torque.

Dewalt does make a good tool; they are popular and hot-selling for a reason. They are positioned as an up-market versions of the regular value-oriented Black and Decker brand. Dewalt tools are pro-like and their signature yellow and black theme helps brand them as construction and job-site ready.

We feel it’s important to be informed on this. When comparing power-tools, don’t immediately assume the Dewalt 20v is the superior choice. Take a look at the output, speed, blows per minute, or what have you for your specific tool. Sometimes the Dewalt 20v Max is the better tool, sometimes it is not. Take a look at the details and make sure you are getting what you pay for.

at the end of the day…

It’s worth mentioning that we’re not discrediting Dewalt here. Their tools are a solid option. Dewalt manufactures a wide variety of power tools, and if you are looking to stay within a particular brand’s ecosystem, Dewalt is a good choice. Choosing the same brand allows you to swap batteries in and out and allows you to use the same charger.

You can often find Dewalt tools on sale or discounted. If you are patient, you can frequently pick up a bargain on Dewalt tools. When factoring in the performance and price, it’s hard to beat a Dewalt 20v max tool that is on sale. Dewalt tools are often the best value and bang for you buck.

In the end, Dewalt 20v max tools are basically 18-volt tools. Dewalt products are very popular, fairly priced, and offer a three-year warranty, whereas most manufacturers offer a one-year warranty. Even though Stanley Black and Decker is a large multinational with factories abroad, Dewalt still resonates as an American brand. If you’re contemplating what brand to choose for your cordless tools, Dewalt’s 20v max lineup of tools is a solid choice, they are capable, and a step-up from value brands in terms of quality.