DeWalt 25mm Snap-Off Blades (3 pack)

Why I reached for these 25mm blades

Snap-off knives are a quiet workhorse in my kit, especially for demolition, packaging, and layout. After a few weeks with these 25mm blades, I’ve come to appreciate how much difference a wider, thicker blade makes when you’re pushing through dense or abrasive material. They aren’t the light, fussy kind you use for craft paper. These are heavy-duty, 25mm-wide blades—about an inch across—with enough spine to stay straight through thick corrugate, roofing underlayment, and foam board without chattering or wandering.

Design and build

Each blade is segmented into seven cutting points, so you get multiple fresh edges per blade. In a three-pack, that’s 21 cutting edges in total. The segments are deeply scored and break predictably at the lines; I never had a segment shear diagonally or leave a jagged nub. The steel is heat-treated and induction-hardened, and that shows up in use more as consistent edge behavior than as flashy longevity numbers—edges don’t chip out prematurely, and they dull evenly without grabbing.

At 0.05 inches thick (roughly 1.3 mm), these are stiffer than many generic snap-offs I’ve used. That thickness matters. A wide, thick blade stays planted on long cuts, especially on double-wall cardboard, rigid foam insulation, and stacked plastic sheeting. It also means you’ll need a bit more force to snap segments compared to a thinner, 18mm blade, but the clean breaks were worth it.

Fit was excellent in the 25mm snap-off knives I own. The blades slid smoothly, locked down firmly, and there was no lateral play when fully extended. If your knife takes standard 25mm blades, you should be fine; if you’re coming from the more common 18mm size, you’ll need a compatible 25mm body.

Performance on real materials

• Cardboard and packaging: This is where these blades shine. I broke down a garage’s worth of shipping boxes—everything from single-wall mailers to thick appliance cartons. The first segment stayed sharp long enough to slice tape cleanly and glide through corrugate without tearing the liner. When it finally lost its bite, a quick snap gave me a fresh edge and I kept going. The extra width helps you cut straight, even through multiple layers.

• Rigid foam and insulation board: With foam board (XPS and EPS), the stiffness helps you track a line and avoid “sawing.” I got clean edges with just a few passes, and the blade didn’t dive or deflect. If you’re cutting wide strips repeatedly, the 25mm format is far more stable than 18mm.

• Flooring and trim tasks: Trimming vinyl plank and scoring laminate underlayment went smoothly. For carpet, a hooked trapezoid blade still wins for me, but these 25mm blades handled light carpet trimming and tack strip foam without fuss.

• Drywall scoring: They score drywall crisply. The wide spine shows its value here—less flex across long scores. That said, if you’re cutting dozens of sheets, the abrasive paper will chew through segments more quickly. The convenience of snapping to a new edge mitigates that.

• Abrasive materials: Cutting roofing felt and fibrous cement board mesh dulled edges faster (expected), but the edges didn’t micro-chip. I’d plan on consuming more segments when working in those materials.

Across all of this, the cutting feel was predictable. No odd hard-soft cycling as the segments wore down, and no burrs that made the blade “scratchy” out of the package.

Snapping segments and safety

Snap-off blades are only as good as their break lines. These break crisply with pliers or a built-in tail snapper. Because of the blade’s thickness, you need deliberate pressure to break a segment; I view that as a positive for control. My routine:

• Retract the blade to expose just one scored line.
• Grip the segment with pliers or use the knife’s snapper.
• Snap away from your body and into a container or thick tape.
• Immediately secure the broken segment in tape or a blade bank for disposal.

Some 25mm knives have a notch that captures the segment for snap-off; if yours doesn’t, pliers are the safer bet. I wouldn’t recommend snapping by hand. Also, if you have smaller hands, the combination of a big 25mm knife and the force needed to break segments may be fatiguing. In that case, an 18mm setup might be more comfortable.

Edge life and consistency

Induction hardening tends to yield predictable edge life rather than dramatically long life, and that’s what I saw. On typical shop and site materials—corrugate, housewrap, foam, plastic strapping—I got plenty of productivity per segment. On abrasive wraps and dusty demolition work, segments went faster, but the ability to reset to a fresh edge in seconds kept me moving. The important part is consistency: each segment felt like the last. That matters more than squeezing out a few extra cuts from a soft batch of steel.

Value and packaging

Three blades with seven cutting points each is a straightforward value proposition. Because the blades are not sharpenable, segment count and steel consistency are what you’re buying. I’d love to see a small disposal sleeve or tube included for snapped segments; as it stands, I used painter’s tape to bundle them before binning. The overall pack weight is light enough to toss into a pouch without noticing, and the blades aren’t oily or messy out of the sleeve.

If you mainly cut light materials once in a while, an 18mm blade might be more economical. If you break down boxes daily, cut insulation, or do layout and scoring on panels, the 25mm format pays for itself in control and speed.

Compatibility notes

These blades fit every 25mm snap-off knife I tried without fuss. They’re standard in width and thickness for the category. Still, it’s worth checking your knife’s size; 9mm and 18mm are more common in office and craft settings, and these will not fit those bodies. If you’re stepping up to 25mm for the first time, make sure your handle has a solid steel channel and a robust lock—these blades reward a sturdy body.

Where they excel

• Heavy-duty box breakdown and shipping rooms
• Long, straight cuts where blade flex hurts accuracy
• Scoring and snapping panels (drywall, foam board)
• Repetitive cuts that benefit from quick edge refreshes
• Users who prefer a stiffer, wider blade for control

Where they’re less ideal

• Delicate or intricate work that favors a 9mm blade
• Extended carpet cutting where a hooked blade is better
• Users with smaller hands who find 25mm handles bulky
• Environments without a safe way to dispose of segments

Final thoughts

What stood out most with these 25mm blades was predictability: consistent edge feel from segment to segment, clean and controlled snapping, and a rigid spine that keeps cuts on track. The induction-hardened edges hold up well in typical shop tasks and dull gracefully in harsher materials. If you’re upgrading from 18mm for more control on thick or layered stock, you’ll notice the difference immediately.

Recommendation: I recommend these blades for anyone doing regular heavy-duty cutting—warehouse and shipping work, shop breakdown, insulation and panel scoring, and general construction tasks where a firm, straight cut matters. They’re a dependable, no-drama consumable with clean snap lines and a sturdy feel. If your work is mostly light-duty or you prefer a smaller knife, you may be better served by an 18mm blade, but for stability and productivity, these 25mm blades are an easy choice.