DeWalt 20V MAX Cordless 6-1/2 in. Sidewinder Style Circular Saw (Tool Only)

Why I reached for this saw

I’ve been hauling a lot of battery tools to small jobs lately—deck repairs, punch-list trim, a bit of attic framing—and I wanted a lightweight circular saw that wouldn’t fight me in tight spaces. The DeWalt 20V circular saw (DCS391) slots into that role well. It’s a 6-1/2 in. sidewinder with a left-side blade, a magnesium shoe, and a brushed motor rated around 5150 RPM. It’s sold as a bare tool, but I’ve already got plenty of 20V MAX batteries, so it was an easy add.

Build and ergonomics

The first thing you notice is balance. At 8 lb bare, it’s not featherweight, but the magnesium shoe and compact form make it feel nimble. With a 5Ah pack onboard, it carries like a framing hammer rather than a boat anchor. The rubber over-molded grip is comfortable, and the handle angle gives decent control when you’re pushing through rips or easing into bevel cuts.

The left-side blade is a win for right-handed users: I can track the cut line without leaning over the motor housing. Lefties may feel the opposite. The shoe is flat and stiff, and it glides well over plywood and framing lumber without the stickiness some painted bases have. I’ve knocked it around enough that a softer alloy would have shown a bend by now; this one has held true.

Controls are straightforward: depth and bevel levers move smoothly and lock positively. The lower guard returns reliably and doesn’t hang up on thin rips—a common annoyance with budget saws. Blade swaps are quick thanks to the spindle lock; there’s nothing fancy here, but it works.

Performance in wood

This is a framing-first saw and it behaves like one. With the included 18-tooth carbide blade, it chews through SPF 2x stock without complaint. I ripped and crosscut dozens of 2x4s and 2x6s for blocking and joists; it maintains speed well unless you lean on it too hard. In 3/4 in. ply and OSB, it tracks straight and the cut face is cleaner than I expected with an 18T blade. Put on a 24T thin-kerf framing blade and runtime improves a bit; step up to a 40–60T finish blade and you’ll get cabinet-grade edges for trim-grade plywood, with the expected trade-off in speed.

You get 2-1/8 in. depth at 90°, which clears 2x lumber easily. At 45°, the saw still gives 1-5/8 in., so it will bevel through a 2x in one pass. Bevel range is 0–50°, and the shoe stays aligned as you tilt; I didn’t see the toe-out that cheaper hinges sometimes introduce. I do wish the bevel scale were more legible in low light, but setting to 45° with a digital angle gauge solved that.

If you work a lot in wet pressure-treated lumber, you’ll feel the brushed motor dig in a bit under load. It doesn’t stall unless you force it, but you’ll get better results letting the saw do the work and keeping a sharp, thin-kerf blade on it. For longer rips in dense sheet goods, a higher-tooth-count blade keeps heat down and reduces tear-out.

Runtime and batteries

Runtime is always the big cordless question. On a healthy 5Ah pack, I got through an afternoon of punch-list cuts: roughly 40–60 crosscuts in dry 2x4 SPF, plus a handful of 8-ft rips in 3/4 in. plywood, before swapping batteries. That’s respectable for a brushed 6-1/2 in. saw. If you’re framing all day, carry two 5Ah packs (or a single 8Ah) and you’ll be fine. Thin-kerf blades and steady feed pressure noticeably extend runtime.

If you only have compact 2Ah packs, expect frequent changes; the saw will run, but it’s not the ideal pairing for continuous work. The good news is the tool sips power once it’s up to speed, so short, intermittent cuts barely dent a larger pack.

Accuracy and setup

Out of the box, my saw’s shoe and blade were square to each other at 90°, and the bevel pointer was within a hair of dead-on at 45°. I always check new saws with a reliable square and adjust the 0° stop screw; this one needed a tiny tweak to dial 90° perfectly. Once set, it held calibration through transport and site abuse.

Line of sight is excellent. The left blade gives you a direct view of the kerf, and there’s enough clearance at the shoe to ride alongside a straightedge without the guard snagging. I’d call the cut line marker “serviceable”: it’s not a precision indicator, but with typical carpenter’s pencil lines it gets you close. For cabinet work, I still scribe, clamp a guide, and use a fine-tooth blade.

If you’re new to circular saws, the included manual won’t teach you much. It covers safety and basic parts but skimps on step-by-step blade changes and bevel technique. A quick video will get you up to speed. Blade swaps are straightforward: disconnect battery, hold the spindle lock, loosen the arbor bolt, mind blade rotation direction, and re-tighten.

Dust, noise, and comfort

It’s a sidewinder, so expect a sharp bark when it spools up, but vibration is well controlled and the handle geometry keeps your wrist in a neutral position. The left-hand blade throws chips left and slightly forward; if you’re right-handed, that keeps most debris off your face, but you’ll still want eye protection. There’s no vac port, so indoor work will get dusty; outdoors, the built-in blower clears the cut line reasonably well.

What it excels at

• Portable framing and carpentry: blocking, decking, studs, roof sheathing
• Quick jobsite cuts without dragging a cord
• Overhead and ladder work where a lighter, compact saw matters
• Clean plywood cuts when paired with a higher-tooth 6-1/2 in. blade

Where it shows its age

• Brushed motor: plenty capable, but it won’t match the runtime or torque of newer brushless 7-1/4 in. models
• Bare tool only: budget-friendly if you’re already on 20V MAX; pricier if you need a starter kit
• Limited dust control: no easy way to capture chips
• Documentation: basic, could be clearer for first-time users

None of these are deal-breakers if you understand the tool’s lane. It’s built for mobility and everyday carpentry, and it hits those notes reliably.

Tips to get the most from it

• Use the right blade for the job. Keep a 24T thin-kerf for framing and a 40–60T for sheet goods and finish cuts.
• Let the saw set the pace. Pushing hard just burns battery and invites deflection.
• Check and set your 0° stop once. It’s a 60-second tune-up that improves accuracy.
• Pair it with 5Ah or larger batteries. Compact packs are fine for occasional cuts, but not for extended sessions.
• Mark your bevels with a digital gauge for precise angled cuts; the pointer is good, a gauge is better.

Value and platform

As a bare tool, the DCS391 makes strong financial sense if you already own DeWalt 20V MAX batteries. You get a durable magnesium shoe, solid cut capacity, and a comfortable form factor that you can throw in the truck without thinking twice. The 3-year limited warranty (with a 1-year free service contract) adds peace of mind. If you’re building a battery ecosystem from scratch, weigh the cost of a kit and consider whether you want to jump straight to a brushless saw for maximum runtime; both routes have merit depending on your workload.

Final take

After several weeks of real jobsite use, the DeWalt 20V circular saw earned a spot in my everyday kit. It’s compact, predictable, and strong enough to handle the bulk of my carpentry tasks without reaching for a corded unit. It won’t replace a full-size brushless 7-1/4 in. saw for all-day structural ripping, and it won’t win any dust-control contests, but as a go-anywhere workhorse that stays accurate and easy to handle, it delivers.

Recommendation: I recommend this saw to anyone already on DeWalt’s 20V MAX platform who needs a reliable, lightweight cutter for framing, decking, and general carpentry, or to homeowners who want a capable, easy-to-use saw for projects and remodels. Pair it with a couple of 5Ah batteries and a thin-kerf blade, and you’ll get a lot of work done with minimal fuss. If you need maximum runtime, torque, or dust collection, consider a brushless 7-1/4 in. upgrade—but for portability and everyday performance at a fair price, this one is a smart buy.