DeWalt DCF850 Impact Driver Review: Compact Power That Punches Above Its Size

Introduction

The DeWalt DCF850 is the brand’s newest and most compact 18V impact driver, and it makes a strong first impression: three speed settings, a weight of about 2.1 lbs without the battery, and a body measuring under 4 inches across. That combination of size and output is what puts it in direct conversation with Milwaukee’s comparable driver, and it is what makes this tool worth a closer look for anyone choosing between the two platforms.

Who This Product Is For

This driver suits buyers who want the smallest, lightest impact driver they can get without giving up meaningful power. It is a natural fit for electrical work, cabinet installs, deck building, and general construction where the tool lives on a belt or in a tight workspace all day. It also matters which battery platform you are already in, since sticking with your existing batteries usually outweighs small performance differences.

Power and Drilling Performance

In testing, the DCF850 handled a 7/8-inch bit with no problem at all, and a 1-inch bit with only a slight slowdown that was barely noticeable. A 1 1/4-inch bit also went through, and even a 7/8-inch auger bit presented absolutely zero issue. The quick-connect collet makes bit swaps fast, spitting out smaller bits on its own when they are loose enough.

Pushed into harder material, a 1 1/2-inch spade bit driven all the way through an old treated 6x6 went through with what could fairly be called an amazing result for a tool this size. The tool heats up under sustained load, reaching around 114 to 118 degrees near the collet in extended testing, which is worth knowing but appears normal for compact impacts running this much power.

Real-World Driving Tests

Against Milwaukee’s comparable driver, the pattern was consistent: the Milwaukee is faster, and the gap is noticeable once you really look at the timing. Driving the same 1 1/2-inch spade bit through thick treated lumber, the Milwaukee beat the DeWalt by a significant margin in repeated tests. The DeWalt is smaller, though, and the power coming out of it is still very impressive for its footprint.

It is worth noting the tests were not perfectly balanced: the DeWalt had been run considerably more, and different batteries and wood variations affected the results. Still, if raw speed on the biggest bits is your top priority, the Milwaukee holds the edge; if compact size matters more, the DeWalt keeps pace remarkably well.

Speed Modes and Control

Level three zips deck screws in with no issue, and level two remains quite quick while being the slowest sensible setting for decking work. Level one is the quirky one: it does not really impact as it drives, instead stopping and then giving another twist at the end, which makes it better suited to very light-duty fasteners.

For fine woodworking-style control, level one falls short, and you would need to drop to level two and feather the trigger. But for electrical plates, machine screws, and other small fasteners, level one is genuinely useful. One standout: the variable speed trigger is among the best seen on an impact driver in a long time, delivering precise control across all modes. Reverse on level one does impact, which helps back out deeper fasteners.

Things to Consider Before Buying

The level-one mode’s lack of true incremental impact is the main trade-off, and the brushless motor produces some noticeable noises under load. Heat build-up during extended heavy drilling is normal but real. And while the tool keeps up on power, the Milwaukee rival is measurably faster on the largest bits.

Buying Advice

If your criteria are the most powerful and fastest driver in the smallest package, know that the DeWalt gives you the smaller tool while the competitor gives you the faster one. For most buyers the decision comes down to which battery platform you already own, and the DCF850 shows DeWalt stepping up significantly with a compact driver that stays competitive in its class.

Conclusion

The DeWalt DCF850 is a genuinely impressive compact impact driver: strong drilling output, an excellent trigger, three useful speed modes, and a body under 4 inches across. Its level-one mode and heat under load are minor quirks rather than dealbreakers. If you are in the DeWalt platform and want a small driver that can still punch deep into treated lumber, this is an easy recommendation.