A cordless oscillating multi-tool is one of the most versatile tools on the job site. It’ll sand a tight corner, cut drywall, cut through nails in wood and scrape old paint. Multi-tools are usually lighter-duty than drills and saws, so many users get on well with smaller batteries, and the right choice can save you money.
We have not tested these batteries ourselves; this guide is based on maker specifications and our own suggestions. If you’re wondering whether a 3.0Ah is enough or if you need to go larger, it sets out the trade-offs based on what you actually do with the tool.
Quick Recommendations
| Use Case | Makita 18V LXT | DeWalt 20V MAX | Milwaukee M18 |
|---|---|---|---|
| Best All-Round | BL1850B 5.0Ah | DCB205 5.0Ah | 48-11-1850 5.0Ah |
| Best for Heavy Use | BL1860B 6.0Ah | DCB206 6.0Ah | 48-11-1860 6.0Ah |
| Smaller pack | BL1830 3.0Ah | DCB204 4.0Ah | 48-11-1840 4.0Ah |
Starter packs by platform
As an Amazon Associate we earn from qualifying purchases. Genuine packs only; check the listing matches your platform before buying (affiliate links).
Before you buy: check that the size, fitting/bore and maximum-rated speed marked on the accessory match what your tool’s manual specifies. We have not physically tested these products; listings are compiled from published specifications. These are affiliate links.
Get the free Power-Tool Battery Compatibility Handbook (PDF)
Which batteries fit which tools — cross-brand, adapters & Ah, decoded.
Why Battery Choice Matters for Multi-Tools
Multi-tools are an exception to the “bigger battery is always better” rule. The makers do not publish runtimes for these tool and battery pairs, and we have not tested them, so we do not estimate them. A 5.0Ah pack simply holds two-thirds more charge than a 3.0Ah pack.
Weight matters on a multi-tool, because you often hold it at arm’s length, overhead or in a tight corner. But check real weights before assuming a smaller pack is lighter: Makita UK lists the 3.0Ah BL1830B at 0.64 kg, about the same as the 5.0Ah BL1850B (0.63 kg), whereas DeWalt US lists the 4.0Ah DCB204 at 1.4 lb against 1.54 lb for the 5.0Ah DCB205.
Best Batteries for Makita Multi-Tools
Best All-Round: Makita BL1850B 5.0Ah
The BL1850B is our pick for mixed multi-tool work. Makita UK lists it at 0.63 kg, no heavier than the 3.0Ah BL1830B, so the extra capacity costs you nothing in weight. Makita does not publish a runtime for this pair, and we have not tested one.
Buy Makita BL1850B on Amazon — 5.0Ah, 18V LXT
Best for Heavy Use: Makita BL1860B 6.0Ah
If you’re doing extended sanding or scraping jobs, the BL1860B is worth considering. Makita UK lists it at 0.66 kg, only 30 g more than the BL1850B. Makita does not publish a runtime for this pair, and we have not tested one.
Buy Makita BL1860B on Amazon — 6.0Ah, 18V LXT
Smaller Pack: Makita BL1830 3.0Ah
The BL1830 is a 3.0Ah pack. If you already own larger batteries for your drills and saws, it can serve as a multi-tool pack, but note that Makita UK lists the BL1830B at 0.64 kg, the same as the 4.0Ah BL1840B and about the same as the 5.0Ah BL1850B, so it does not save weight.
Buy Makita BL1830 on Amazon — 3.0Ah, 18V LXT
Explore all Makita 18V LXT batteries on the Makita 18V LXT Battery Compatibility page.
Best Batteries for DeWalt Multi-Tools
Best All-Round: DeWalt DCB205 5.0Ah
The DCB205 is DeWalt’s 5.0Ah 20V MAX pack (US part number; DeWalt’s UK 5.0Ah 18V XR pack is the DCB184) and a sensible all-rounder for DeWalt multi-tool users. DeWalt US lists it at 1.54 lb, against 2.25 lb for the 6.0Ah DCB206. DeWalt does not publish a runtime for this pair, and we have not tested one.
Buy DeWalt DCB205 on Amazon — 5.0Ah, 20V MAX
Best for Heavy Use: DeWalt DCB206 6.0Ah
The DCB206 is DeWalt’s 6.0Ah pack, for sanding large areas or long scraping jobs. DeWalt US lists it at 2.25 lb, so you will notice the weight more; choose it if continuous runtime matters more than holding comfort.
Buy DeWalt DCB206 on Amazon — 6.0Ah, 20V MAX
Best Lightweight: DeWalt DCB204 4.0Ah
The DCB204 is a 4.0Ah pack, slightly lighter than the 5.0Ah DCB205 (DeWalt US: 1.4 lb vs 1.54 lb). It suits detail sanding, cutting corners and finish work where control matters more than maximum runtime.
Buy DeWalt DCB204 on Amazon — 4.0Ah, 20V MAX
See all compatible DeWalt 20V MAX batteries on the DeWalt 20V MAX Battery Compatibility page.
Best Batteries for Milwaukee Multi-Tools
Best All-Round: Milwaukee 48-11-1850 5.0Ah
The 48-11-1850 is Milwaukee’s US M18 REDLITHIUM XC5.0 pack (Milwaukee’s UK 5.0Ah M18 pack is the M18 B5) and the sensible all-rounder for Milwaukee multi-tool users. Milwaukee does not publish a runtime for this pair, and we have not tested one.
Buy Milwaukee 48-11-1850 on Amazon — 5.0Ah, M18
Best for Heavy Use: Milwaukee 48-11-1860 6.0Ah
The 48-11-1860 is Milwaukee’s US M18 REDLITHIUM XC6.0 pack, for production-level sanding or scraping where you want fewer battery swaps. Weight will be more of a factor on overhead work.
Buy Milwaukee 48-11-1860 on Amazon — 6.0Ah, M18
Smaller Pack: Milwaukee 48-11-1840 4.0Ah
The 48-11-1840 is Milwaukee’s US M18 REDLITHIUM XC 4.0 pack. It may not save much weight: Milwaukee UK lists its 4.0Ah and 5.0Ah M18 packs (M18 B4, M18 B5) at the same 0.7 kg. Choose it if you already own one.
Buy Milwaukee 48-11-1840 on Amazon — 4.0Ah, M18
View all compatible Milwaukee M18 batteries on the Milwaukee M18 Battery Compatibility page.
Full Comparison Table
| Battery Model | Platform | Capacity | Best For | Buy Link |
|---|---|---|---|---|
| Makita BL1850B | 18V LXT | 5.0Ah | Mixed multi-tool tasks | Buy |
| Makita BL1860B | 18V LXT | 6.0Ah | Extended sanding, continuous use | Buy |
| Makita BL1830 | 18V LXT | 3.0Ah | Light duty, detail work | Buy |
| DeWalt DCB205 | 20V MAX | 5.0Ah | Mixed multi-tool tasks | Buy |
| DeWalt DCB206 | 20V MAX | 6.0Ah | Extended sanding, production work | Buy |
| DeWalt DCB204 | 20V MAX | 4.0Ah | Balanced weight and runtime, detail work | Buy |
| Milwaukee 48-11-1850 | M18 | 5.0Ah | Mixed multi-tool tasks | Buy |
| Milwaukee 48-11-1860 | M18 | 6.0Ah | Extended sanding, high-demand continuous use | Buy |
| Milwaukee 48-11-1840 | M18 | 4.0Ah | Detail sanding, control | Buy |
Watch: Video Guide
Frequently Asked Questions
Do cordless multi-tools drain batteries quickly?
The makers do not publish runtimes for these tool and battery pairs, and we have not tested them, so we do not estimate them. Multi-tools are usually lighter-duty than drills, saws or angle grinders, so a smaller pack on the multi-tool and larger packs for high-demand tools is a sensible strategy.
What’s the best lightweight battery for multi-tools?
A 3.0–4.0Ah pack is often suggested for detail work, overhead cutting or finish sanding, but check the weights first: Makita UK lists the 3.0Ah BL1830B at 0.64 kg, about the same as its 5.0Ah BL1850B (0.63 kg), and Milwaukee UK lists its 4.0Ah and 5.0Ah M18 packs at the same 0.7 kg. DeWalt’s 4.0Ah DCB204 is slightly lighter than its 5.0Ah DCB205 (1.4 lb vs 1.54 lb, DEWALT US).
Does sanding drain the battery faster than cutting?
Possibly, but we have no maker data on it and have not measured it. Runtime depends on the accessory, the material and the speed setting, so we do not give a percentage.
Can I use a larger battery on my multi-tool?
Yes, if it is a pack from the tool’s own platform. A larger battery will simply extend your runtime; the real question is whether its extra weight is worth it for your work.
How long do multi-tool batteries last?
The makers do not publish a lifespan in years for these packs, and we have not tested one. Lithium-ion packs lose capacity with use and age. Store batteries in a cool, dry place, and follow your battery maker’s storage and charging instructions.
How we compile this guide
We cross-reference compatibility details against manufacturer specifications where available, official tool manuals, and the physical standards that govern fitment (bore sizes, arbor diameters, voltage platforms, connector types). We prioritise primary sources over retailer listings, flag anything we can’t confirm, and re-verify the data on a regular cycle. Where we give a buying recommendation, we tell you the reasoning — not just the link. More on our method →
