Impact drivers compared by torque, speed and weight

How to read impact driver figures

Makers publish three performance figures for an impact driver: maximum torque, top speed and impacts per minute. Torque is the one listings lead with, and the one most often overrated. It tells you how large a fastener the driver can turn before it stalls, not how fast it drives an ordinary screw, and it is measured by each maker its own way. Read the torque column as "enough or not enough for my largest fastener", not as a ranking. This page is research-based, from the makers' pages and the current listings; we have not run these drivers against each other.

Torque, converted

Every maker here states torque in in-lb. The table converts to ft-lb by dividing by 12 and rounding, so you can compare them with the impact wrenches and ratchets elsewhere on this site.

The DCF860B's 2,500 in-lb is 37 percent more than the DCF845B's 1,825 in-lb. That gap matters if you drive long lag bolts into framing every week. For decking screws, cabinets and furniture, every driver here has more torque than the screw needs, and the lower settings of a three-speed driver are what keep you from snapping heads or sinking screws too deep. Our torque units page explains in-lb and ft-lb in more detail.

Torque for the weight: M12 against M18

Milwaukee is the one maker here that states weights for both of its drivers, so we can do the arithmetic. The M18 2953-20: 2,000 in-lb on 2.2 lb, about 909 in-lb per pound. The M12 3453-20: 1,500 in-lb on 2 lb, 750 in-lb per pound. The M18 gives more torque for each pound you hold; the M12 gives the lower total weight, plus a body Milwaukee states at 5 in. long. Over a day of overhead work, those few ounces count; for a few lag bolts they do not. Milwaukee does not say on either page whether the weight includes a battery, and M12 and M18 batteries differ in size, so check the figure with the battery you will fit before you rely on the gap. Choosing between the two Milwaukee systems in general is covered on Milwaukee M12 or M18.

DEWALT's pages for its three drivers, as we read them, state no weight. The weight column shows the listing's figure for those rows, which may include packaging; treat it as approximate.

Speed and impacts per minute

Top speed is no-load spin: how fast the bit turns before it meets resistance. Once the screw resists, the hammer mechanism starts and the impacts-per-minute figure takes over. Only CRAFTSMAN states an IPM figure on the pages we read, 3,100 for the CMCF800. Within one maker, a higher top speed generally means faster driving of small and medium screws; across makers, measurement methods differ, so treat a few hundred RPM as a tie.

A decision rule

1. Own batteries already? Pick from your platform: DEWALT 20V MAX (DCF860B, DCF845B, DCF850B), Milwaukee M18 (2953-20), Milwaukee M12 (3453-20).
2. No batteries yet? Pick a kit: the CRAFTSMAN CMCF800C1 or the DEWALT DCF787D1. If you will want a drill too, a two-tool kit is usually the simpler start; see cordless combo kits compared.
3. Largest fastener a long lag bolt into framing, often? Favour the higher torque rows. Mostly cabinets, decks and furniture? Favour a three-speed model or a lighter, shorter one.

Not sure an impact driver is the tool you need? See drill or impact driver.

Reading the table

A figure with a mark comes from the maker's page for that model, linked under Sources; the torque cells are our conversion of the maker's in-lb figure. Other cells are from the current listing. The DCF787D1 row is listing-only: we could not read a DEWALT page for that kit. "Sold as: Tool only" means the maker or listing says no battery or charger is included.

What this page does not tell you

We have not used these drivers against each other, and we do not rank them. We do not measure real driving speed, runtime, noise or durability. For fastener sizes and pilot holes, follow the fastener maker's instructions.