Dewalt 20V Atomic DCD799 Hammer Drill Review

Dewalt DCD799 Angle 5

Quick take

The Dewalt 20V Atomic DCD799 Hammer Drill is ideal for homeowners or trades workers who value a drill with a good size, weight, and performance balance. The DCD799 is incredibly lightweight and compact for an 18V hammer drill, as should be expected from Dewalt’s Atomic-branded lineup that’s designed to cast a small shadow. It also drills and drives reasonably fast for the size. It won’t win speed contests since flagship-level drills take that crown. Instead, it hits the needed criteria for use outside the job site. Namely, it’s easy to use with the size and weight and easily finishes light and medium-duty jobs. Woodworkers may also want to consider the DCD799 if they want something more powerful than a 12V drill.

Brand Dewalt
Platform 20V Atomic
Motor Brushless
Speeds 2
Torque in-lbs Not advertised
BPM 28,050.0
Clutch settings 15
Chuck size 1/2"
Same as DCD799B

Global rankings

18 models tested

Drilling speed (sec.)17.211
Driving speed (sec.)12.710
Torque (in-lbs)Not advertisedNot ranked
Bare weight (lbs)2.548
Drilling Noise (dBA)88.29

Editorial opinion

Methodology used: Heavy duty

Editorial rating

4.02 / 5 stars


  • Exceptionally lightweight and compact
  • Includes a hammer drill functionality
  • Brushless motor
  • Long warranty


  • Plastic chuck sleeve isn’t as durable as metal

Recommended configuration


Includes (2) Max 12V 3Ah battery

Series lineup

Model #PlatformAction ModesMax Torque (in-lbs)Review
Dewalt DCD70920V AtomicDrill, hammerNot advertisedFull review
Dewalt DCD79920V AtomicDrill, hammerNot advertisedFull review
Dewalt DCD80020V Max XRDrill onlyNot advertisedFull review
Dewalt DCD80520V Max XRDrill, hammerNot advertisedFull review

Lab results

Drilling speed

Drilling speed total time (drill mode, sec.): 17.2
Drilling speed average time (drill mode, sec.): 3.4
Drilling speed total time (hammer mode, sec.): 13.9
Drilling speed average time (hammer mode, sec.): 2.8
Hammer mode speed improvement: 19.2%

The DCD799 impresses when considering the drilling speed for the size. No compact hammer drill can compete on speed with bulkier and more powerful flagship models. However, the DCD799 is one of our test fleet’s fastest compact hammer drills.

Importantly, it sustained high RPMs throughout the hole depth to clear chips and avoid bogging down.

The hammering functionality performed reasonably well at improving drilling speeds in stacked lumber. On average, we expect 20.0% or better speed improvement when using the hammer drill over the standard drill mode.

We also tested the DCD799 using a range of forstner, spade, and auger bits. We started to feel the DCD799 was underpowered once boring holes 3/4 inch and wider with the forstner and spade bits. It wasn’t underpowered in that it couldn’t complete each task. Instead, we had to drop to the low setting for additional torque to finish the job.

Compare drilling speed test results

Driving speed

GRK total driving time forward (sec.): 12.7
GRK average driving time forward (sec.): 2.5
GRK total driving time reverse (sec.): 9.9
GRK average driving time reverse (sec.): 2.0

The DCD799 is powerful enough to drive structural screws and lag bolts quickly. Again, it isn’t as performant as drills designed for use on the job site. But context is essential when reviewing the driving speed results and determining how much speed matters.

The DCD799 finished 5 1/8 inch GRK RSS fasteners with an average time of 2.4 seconds per screw. The top-performing hammer drills in our test fleet finished with an average of 1.3 to 1.5 seconds per screw. We’ll let our readers determine if the speed difference is worth the higher cost of moving to a faster drill.

Compare driving speed test results


Dewalt DCD799 RPM Chart

Max RPM speed 2: 1,635.0
Max RPM speed 1: 439.0

The measured RPM output for the DCD799 is comparably low, explaining some of the speed performance against faster drills in our test fleet. A higher RPM output profile throughout its transmission settings would improve the DCD799’s speed under load.

Compare drill RPM test results


Advertised max torque (in-lbs): Not advertised
Advertised max torque (ft-lbs): Not advertised

Dewalt no longer advertises the torque of its drills and we currently don’t test torque on a torque meter in-house, like we do for impact drivers.

Compare drill torque


Dewalt DCD799 Chuck Closeup

Chuck size: 1/2″
Chuck sleeve material: Plastic

While an all-metal chuck is more durable, the DCD799’s ratcheting chuck works well with its plastic chuck sleeve and metal three-jaw design. Critically, we didn’t experience any instances of the chuck loosening throughout testing.

Motor & BPM

Dewalt DCD799 Drill Modes

Motor type: Brushless
Action modes: Drill, hammer
Advertised blows per min. (speed 2): 28,050.0
Advertised blows per min. (speed 1): Not advertised
Variable speed trigger: Yes
Kickback control technology: No
Trigger draw length (in.): 0.375

Dewalt designed the DCD799 with a brushless motor, improving its longevity and efficiency over brushed motors, commonly found in cheap power tools.

There are two action modes. The drill mode disengages the clutch for unrestrained torque output. The hammer drill mode also disengages the clutch but layers in a hammering mechanism that impacts at a rate of 28,050.0 blows per minute (BPM).

You can review our drilling speed tests below, where we measure the speed improvement offered using the hammer drill mode.

There is no kickback control technology, which is a minor letdown. The DCD799 is right on the cusp of being a highly powerful drill. Wrist injuries can occur at this power tier, highlighting why kickback control could be valuable. Some of the best Milwaukee drills included kickback control technology.

Compare drill motors

Clutch & speed settings

Dewalt DCD799 Clutch & Speed

Speed settings: 2
Clutch settings: 15

The DCD799 includes a standard two-speed transmission that runs the drill in the low or high setting in all drill modes and clutch settings. Setting the drill to the drill mode in the low setting generates the maximum torque output.

There are 15 total clutch options to tune the torque output for a wide range of tasks. 15 options are fewer than some hammer drills offer. Still, 15 is more than most people will need in practice.

Driving without stripping threads or avoiding cam-out rarely requires precisely finding the single correct clutch setting. Hitting close to the correct torque output works most of the time, and there are no improvements in achieving that outcome with more clutch settings than are needed.

Compare drill clutch and speed settings

Charging time

Dewalt DCD799 Fuel Gauge

Charger tested: Dewalt 20V Max (DCB115)
Charging time 2Ah battery (min.): 59.0
Charging time 4Ah battery (min.): Not tested
Charging time 5Ah battery (min.): 139.0
Charging time per Ah (min.): 28.7
Fuel gauge: On battery

The Dewalt charger included with most kits (model DCB115) isn’t fast. Our tests took 59.0 minutes to top off a Max 2Ah battery and 139.0 minutes to charge a Max XR 5Ah battery. Expect that this charger will charge batteries at approximately 28.7 minutes per Ah. Faster chargers charge batteries at 20.0 or fewer minutes per Ah.

Nicely, the DCD115 works with Dewalt’s 12V and 20V platform batteries, conveniently saving space in your shop if you have several tools in the Dewalt ecosystem.

Compare drill charging test results

Design & ergonomics

Stands upright (no battery): Yes
Stands upright (w/ battery): Yes
Grip material: Rubber overgrip
Magnetic holder: No
Bit holder: No
Belt hook: Yes
Lanyard compatible: Yes

The DCD799’s handle leans slightly forward to orient the drill on the correct plane when drilling. However, the combination of the angle for the handle and the head isn’t as aggressive as some heavier-duty drills. A more aggressive stance ensures the drill remains flat when rolling your wrist forward and applying extra pressure with your arm lined up behind the drill.

A rubber overmold around the grip provides the necessary friction for added grip and shock absorption under load.

There is no bit holder or magnetic plate to hold fasteners onboard, but both features can be purchased separately from third parties.

Lastly, an all-metal belt hook is included in the box and can be mounted on either side of the base in one of the available mounting slots.


Dewalt DCD799 On Scale

Bare weight (lbs): 2.54
Weight w/ 2Ah battery (lbs): 3.34
Weight w/ 4Ah battery (lbs): Not tested
Weight w/ 5Ah battery (lbs): 3.96

One standout feature is the weight for a hammer drill. It weighs 2.54 lbs in its bare form and retains a lightweight status compared to other hammer drills in our test fleet with a battery attached.

We tested different battery configurations since the working weight can differ meaningfully from the bare tool weight. We recommend combining the DCD799 with Dewalt’s 20V Powerstack 1.7Ah battery, which weighs less, has a smaller footprint, and runs longer than Dewalt’s 20V Max 2Ah battery, a solid alternative for a svelte setup.

Or pair the DCD799 with Dewalt’s 20V Max XR 5Ah battery for a longer run time and improved drilling performance if weight is less of a concern.

Compare drill weight test results


Dewalt DCD799 Footprint1
Dewalt DCD799 Footprint2

Max height (in.): 9.125
Max width (in.): 3.125
Chuck to back length (in.): 6.500
Base length (in.): 4.500
Base width (in.): 3.125

The DCD799 is incredibly compact compared to other hammer drills, a class of drills that is almost always bulky since a hammering mechanism must be designed into the head. Notably, the tip-to-tail length is far shorter than competing 18V models and improves upon the footprint of prior-generation Atomic hammer drills.

Compare drill footprint test results

Drilling clearance

Min. interior width clearance (in.): 8.125
Min. top edge clearance (in.): 1.500
Min. interior 45-deg. clearance (in.): 6.625

Since the DCD799 sits within the Atomic lineup, we expected it to perform well in our clearance tests. Notably, the DCD799 is incredibly short for a hammer drill from tip to tail. This sizing helps it fit easily between two vertical boards and in tight corners.

Compare drilling clearance test results

Auxiliary arm

Auxiliary arm: No

The DCD799 doesn’t include an auxiliary handle to control recoil and enhance stability during heavy-duty drilling tasks. The DCD799’s power profile is on the verge of being powerful enough that including an auxiliary arm would be helpful to avoid wrist injuries.

Understandably, Dewalt wouldn’t include one in the box, but we’ll side with consumers and say that not including an auxiliary arm is a slight letdown.

Check out the Milwaukee M18 Fuel 2904-20 Hammer Drill or Makita 18V LXT XPH14Z Hammer Drill if you want a more powerful drill with an auxiliary arm.


Dewalt DCD799 Noise Chart

Max no-load noise (dBA): 79.5
Max drilling noise (dBA): 88.2

Under load with the hammer drill engaged, the DCD799 is moderately loud. We measured 88.2 dBA of noise when boring holes in lumber with the DCD799. This level rivals the noise output of the best impact drivers, which are also harmful with prolonged exposure.

Compare drill noise test results


Dewalt DCD799 Light Wall
Dewalt DCD799 Light Closeup

Light: Yes
Light location: In base
Light positions: 1
Customizable light settings: None
Light count: Single LED
Light active time (sec.): 20.0

The single in-base light shines upward and illuminates a sizeable area where it is focused. Still, lights near the trigger that shine directly forward are more versatile and always precisely illuminate the intended location.

There are no advanced light features, such as a spotlight mode or multi-position light, which some of the best Dewalt drills include.


Tool warranty (years): 3
Battery warranty (years): 3

Dewalt stands behind the durability of its drills with exceptionally long warranties. The DCD799 has a three-year warranty. Dewalt’s 20V Max batteries include a three-year warranty.

Dewalt also offers free maintenance and replacement of worn parts for one year for the DCD799.

Picture of Nathan Hamilton
Nathan Hamilton
Nathan Hamilton is the founder of DIY Gear Reviews and a recognized expert in the home and DIY space. He has over 200 bylines covering topics such as power tools, hand tools, and woodworking. Nathan is the strategic director for DIY Gear Reviews, deciding everything from the content covered to designing the testing methodologies for lab-tested reviews. He can be emailed at


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