DeWalt cordless impact driver buying guide

Updated: 22 October 2026

You already know the brand. The decision is which bare DeWalt 18 V body to clip onto the batteries in the van, and whether the amazon.co.uk figure is the whole spend.

You already know the brand. The decision is which bare DeWalt 18 V body to clip onto the batteries in the van, and whether the amazon.co.uk figure is the whole spend. This DeWalt cordless impact driver buying guide takes that in order: the packs you own, the mechanism, the length, then the mode dial. Saved prices and the four-row table sit on the DeWalt cordless impact driver comparison. Listings were saved on 20 October 2026. These tools were not lab-tested. A qualifying purchase can earn a commission at no extra cost to you.

Our top picks

Badge	Product	Mechanism	Speed modes	Length	Note	Price	Offer
Best overall	DeWalt DeWalt DCF887N	Brushless impact	3	135 mm	9.2	about £59.95	View offer
Best value	DeWalt DeWalt DCF850N	Compact brushless	3	101 mm	8.0	about £98.43	View offer
Alternative	DeWalt DeWalt DCF870N	Hydraulic oil-pulse	3	101 mm	6.6	about £184.99	View offer

Best overall

DeWalt DeWalt DCF887N

9.2/10about £59.95

View offer

Best value

DeWalt DeWalt DCF850N

8.0/10about £98.43

View offer

Alternative

DeWalt DeWalt DCF870N

6.6/10about £184.99

View offer

On this page

1.Start with the batteries you already own
2.Mechanical torque or a hydraulic driver
3.Length and the mode dial
4.Read the part number, not the stray model field

Start with the batteries you already own

All four kept listings are bare bodies on the 18 V XR platform. The DCF887N-XJ is about £59.95, the DCF840N-XJ about £78.00, the DCF850N-XJ about £98.43, and the DCF870N-XJ about £184.99. None of those prices includes a battery or a charger. If a pack is already on the shelf, the body is the purchase. One UK reviewer of the DCF887 says a 5 Ah pack lasts their working day, which is one person's day. You add a pack and a charger before the first screw. 20V MAX on an American page is a marketing voltage. The DCF840 GB manual lists DCB181 to DCB189 and FlexVolt DCB546, DCB547, and DCB548. Match those codes on a UK listing before you compare body prices.

Mechanical torque or a hydraulic driver

The DCF887 and the DCF850 are conventional brushless drivers with three modes and about 205 Nm. The DCF850 manual prints 206.2 Nm. The DCF840 is one speed: DeWalt UK and the GB manual say 192 Nm, while Amazon also prints 200 Nm. Use 192 Nm. The DCF870 is a hydraulic oil-pulse driver at 56 Nm and 500 W. Those figures describe different mechanisms. Take the DCF870 when noise is the reason and 56 Nm covers the screws. UK reviews call it quieter. This comparison did not measure noise. For long timber screws, stay with the DCF887, DCF850, or DCF840. Holes and a clutch belong on a combi, on the impact driver versus combi drill page.

Testsieger

DeWalt DeWalt DCF887N

9.2/10about £59.95

View offer

Length and the mode dial

The DCF850 bullets say about 101 mm and 0.95 kg without a battery. The DCF887 is about 135 mm. One UK reviewer could not get that longer body into a gap under 20 cm. If the screw sits between joists, reviewers describe the DCF850 as the body that kept three speeds. You pay about £98.43 for that nose. The mode dial is a separate choice. Reviewers of the DCF887 say mode 1 is too soft and mode 2 is too fierce on hinge screws. Precision Drive pauses as the head seats, then impacts slowly. If the fastener stalls, select mode 2. The DCF840 has no dial, so the trigger is the only control. How the modes feel is on the how to use a DeWalt impact driver page.

Read the part number, not the stray model field

Specification cells on these listings name a different product. The DCF887N model field says DCF850NT-XJ. The DCF840N field says DCF850E2T-QW. A bare DCF887 row also shows a 2 Ah battery, which the title contradicts. The DCF850 weight cell says 1 g, and other cells say natural latex and faux leather. Ignore them. Buy the part number in the title: DCF887N-XJ, DCF850N-XJ, DCF840N-XJ, or DCF870N-XJ. The DCF887 and DCF870 listings say three years. The DCF840 listing does not state a term. DeWalt UK often states one year, extending to three if you register. The Consumer Rights Act 2015 still lets you reject faulty goods, generally within 30 days. One DCF887 buyer lacked the belt-hook screws and could not register the model number.

Common questions

I already own 18 V XR batteries. Which body do I buy?

If the longer body reaches the screw and you want three modes, start with the DCF887N at about £59.95. Move to the DCF850N at about £98.43 when the nose has to be about 101 mm. Take the DCF870N at about £184.99 when noise is the problem and 56 Nm is enough. The DCF840N is one speed, and 4.5 from 38 ratings is a thin line.

Is 56 Nm on the DCF870 a weaker DCF887?

The DCF870 is a hydraulic oil-pulse driver. Its 56 Nm and 500 W come from DeWalt data and the amazon specification. The DCF887's about 205 Nm is a conventional impact figure. The two numbers describe different mechanisms, so the hydraulic body is a noise purchase when 56 Nm covers the fastening. It is a poor buy when you wanted the conventional torque class at a lower price.

Does the DCF840's single speed matter?

It matters on a small screw or thin material, because the trigger is the only control. Reviewers already find mode 1 too soft and mode 2 too fierce, so one speed will not pause for a hinge. For long timber screws, one speed can be enough if you accept 192 Nm from the GB manual and 38 ratings. Check the part number DCF840N-XJ. The model field names a different body.

Can I use a US 20V MAX battery?

These bodies are sold in the UK as 18 V XR. 20V MAX on an American page is a marketing voltage, not the UK listing. The DCF840 manual names DCB181 to DCB189 and FlexVolt DCB546, DCB547, and DCB548. Match the pack code on amazon.co.uk. A US page in inches is not evidence of the UK price, the star line, or which charger you need.

What should I ignore on the amazon specification table?

Ignore a model field that names another body, a 2 Ah cell on a bare DCF887, a weight of 1 g, natural latex, faux leather, the word Brush beside a brushless bullet, and impact wrench in an included-components row. Use the part number in the title. Where the DCF840 listing prints 200 Nm and the GB manual prints 192 Nm, use 192 Nm. Drilling-capacity cells do not turn these hex drivers into combi drills.

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