DeWalt Cordless Circular Saw Reviews: DCS391 vs DCS570 vs DCS578
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DeWalt Cordless Circular Saw Reviews: DCS391 vs DCS570 vs DCS578
Choose the DCS391 for lighter-duty cuts in sheet goods, the 7-1/4-inch DCS570 for a versatile 20V saw that can handle typical framing lumber, and the 60V FLEXVOLT DCS578 when you need more cutting capacity and sustained power for demanding work. The key trade-off is not just blade size: it is how often you cut thick stock, whether your batteries match the saw, and how much weight you want to manage.
At a glance: capacity, bevels, and batteries
Capacities below are nominal manufacturer specifications. Actual runtime depends on battery capacity and condition, material, blade sharpness, and how hard the saw is pushed. Bare-tool weights exclude the battery and blade.
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| Model | Platform and blade | Cut depth at 90° | Bevel range | Bare-tool weight | Best fit |
|---|---|---|---|---|---|
| DCS391 | 20V MAX, 6-1/2 in. | 2-1/8 in. | 0–50° | About 7 lb | Sheet goods, trim stock, and lighter cutting |
| DCS570 | 20V MAX, 7-1/4 in. | 2-9/16 in. | 0–57° | About 7.5 lb | General-purpose cuts and common framing lumber |
| DCS578 | 60V MAX FLEXVOLT, 7-1/4 in. | 2-7/16 in. | 0–57° | About 8.2 lb | Frequent, demanding cuts and thicker stock |
Weights vary by configuration and published measurement method; adding a battery increases the carry weight. Check the exact tool listing and manual before buying, especially if a particular depth or bevel setting is essential.
Where the three saws differ in real work
DCS391: lighter cuts and easier handling
The DCS391’s 6-1/2-inch blade and 2-1/8-inch maximum depth at 90° suit plywood, OSB, and many other sheet materials. It can also cut a nominal 2-by-4 across its 1-1/2-inch thickness at 90°, with depth to spare. That makes it a sensible choice for occasional home projects, particularly when you already own compatible 20V MAX batteries.
Its limit shows up when you want extra capacity for angled cuts or thicker stock. The 0–50° bevel range is adequate for many jobs, but it gives you less adjustment than the other two. For a large volume of framing cuts, the smaller blade and lower capacity may make the work slower or require more careful setup.
DCS570: the practical 7-1/4-inch 20V choice
If you are searching for a DeWalt cordless circular saw 7 1/4 inches, the DCS570 is the straightforward general-purpose option in this comparison. Its 2-9/16-inch depth at 90° covers common framing lumber, including a 2-by-4, and its 0–57° bevel range adds flexibility for angled cuts. It uses the 20V MAX platform, so it can be an easier fit for a shop already invested in those batteries.
That does not make it equivalent to a corded saw or a higher-power platform in every situation. Dense lumber, a dull blade, or repeated long cuts can drain a battery quickly and slow the cut. Use a sharp, material-appropriate blade and let the saw reach speed before feeding it into the work.
DCS578: more power for sustained, demanding work
The DCS578 is a 60V MAX FLEXVOLT saw with a 7-1/4-inch blade and 0–57° bevel adjustment. Its 2-7/16-inch listed depth at 90° is slightly less than the DCS570’s, so the DCS578 is not automatically the winner on maximum depth. Its appeal is the higher-power FLEXVOLT platform for users making frequent cuts in framing lumber or other demanding material.
FLEXVOLT batteries are designed to work across compatible 20V MAX and 60V MAX tools, but a 60V tool requires an appropriate FLEXVOLT battery. That battery adds expense and weight. If your cuts are mostly occasional plywood breakdowns, the added power may not repay that cost; if the saw is a daily framing tool, it can be a more compelling upgrade.
Pick by project, not by blade size alone
| Your situation | Best starting point | Why |
|---|---|---|
| Mostly plywood or OSB; occasional DIY use | DCS391 | Enough depth for common sheet goods, with a smaller blade and 20V battery platform |
| One saw for repairs, decking, and routine framing | DCS570 | 7-1/4-inch blade, useful bevel range, and compatibility with 20V MAX batteries |
| Frequent framing or repeated cuts in demanding stock | DCS578 | 60V FLEXVOLT power is better suited to sustained heavy work |
| You own 20V batteries but no FLEXVOLT battery | DCS391 or DCS570 | Using batteries you already have can make the overall purchase more economical |
| You need maximum bevel flexibility among these options | DCS570 or DCS578 | Both are specified for bevels up to 57°, versus 50° on the DCS391 |
For a simple capacity check, compare the saw’s stated depth with the actual thickness you need to cut. A standard 2-by-4 is 1-1/2 inches thick, so all three have sufficient nominal depth for a straight crosscut. For a bevel, available depth decreases; check the manual’s bevel-capacity chart rather than assuming the 90° figure still applies.
Runtime: what specifications cannot tell you
There is no single runtime figure that applies to every job: cutting a few short pieces of dry pine is very different from repeatedly ripping thick, dense stock. Battery amp-hour capacity, blade condition, feed pressure, and the number of starts and stops all affect how long you can work. The DCS578’s higher-power platform helps with demanding work, but it does not make battery capacity irrelevant.
- For sheet breakdown: Plan the layout to reduce unnecessary cuts, and use a straightedge or track-compatible guide where appropriate. Long, continuous cuts consume more energy than short cuts.
- For framing: Keep a charged spare battery available if you are cutting throughout the day. A battery that is nearly depleted can interrupt work even when the saw itself is capable.
- For dense or treated lumber: Use a sharp blade rated for the material. Forcing the saw through a cut increases heat and battery demand and can worsen cut quality.
When comparing kit and bare-tool prices, treat battery cost as part of the saw’s real cost. General market prices vary by retailer, kit contents, and promotions; compare the included battery capacity and charger rather than judging the price by the tool name alone.
Ownership details that affect cut quality
On any circular saw, the blade is a wear item and often the first thing to check when cuts become slow, rough, or prone to burning. Match blade type and tooth count to the material and finish you need, and replace a damaged or persistently dull blade rather than compensating with extra force. Keep the base plate clean so it slides smoothly, and clear dust from the saw after use according to the manual.
Support sheet goods close to the cut line without pinching the blade as the offcut falls. Set the blade depth only as far below the material as the job requires, secure the work, and keep hands clear of the cut path. Before changing a blade or adjusting the saw, remove the battery. These habits help prevent binding and reduce unnecessary wear on both the blade and tool.
Bottom line
The DCS391 is a reasonable match for lighter work and sheet goods when compact handling and existing 20V batteries matter most. The DCS570 is the most balanced pick for buyers who want a 7-1/4-inch DeWalt cordless circular saw on the 20V platform for regular home projects and framing. Choose the DCS578 when demanding cuts and sustained work justify a FLEXVOLT battery and the added weight—not simply because its platform number is larger.
