How to Cut a 4×4 With a Circular Saw (Two-Pass Method)
A 7 1/4-inch circular saw cuts about 2 1/2 inches deep — not enough for a 4×4’s full 3 1/2-inch thickness — so a single pass will never get through. You need the two-pass (flip-cut) method: cut from opposite faces along matching lines. Skipping this and forcing one pass risks a stalled blade and kickback, especially near the end of the cut. This guide covers marking all four faces accurately, setting blade depth, and completing the flip cut without splintering or misalignment.
Affiliate disclosure: this post contains Amazon affiliate links. As an Amazon Associate we earn from qualifying purchases.
Why a Circular Saw Can’t Cut a 4×4 in One Pass
A standard 4×4 is actually 3 1/2 inches by 3 1/2 inches (the “4×4” is the nominal, rough-cut size before milling). Most circular saws use a 7 1/4-inch blade, and even at full depth setting that blade only reaches about 2 1/2 inches into the material — roughly a full inch short of cutting all the way through. That gap is why every reliable method for cutting a 4×4 with a circular saw involves cutting partway through, then finishing the cut from the opposite face.
📊 A 7 1/4-inch circular saw blade has a maximum depth of cut of roughly 2 1/2 inches at 90 degrees — about 1 inch short of a 4×4’s full 3 1/2-inch thickness. — Source: The Home Depot, Circular Saw Buying & Use Guide
If you own a larger saw — some worm-drive models take an 8 1/4-inch blade — you can get closer to a single-pass cut, but the two-pass method below works with any 7 1/4-inch saw, which is what most homeowners already own. For a look at how a smaller-bladed saw compares, see our breakdown of how much a 7 1/4-inch miter saw blade can actually cut on a 4×4.
Tools and Materials You’ll Need
- 7 1/4-inch circular saw, corded or cordless — see our top picks by spec if you’re shopping for one
- Carbide-tipped 24T or 40T blade rated for the lumber type (framing lumber, cedar, pressure-treated)
- Speed square or combination square
- Tape measure and pencil
- Clamps or a stable pair of sawhorses
- Masking tape (optional, reduces splintering on the exit side)
- Safety glasses and hearing protection
How to Cut a 4×4 With a Circular Saw: Two-Pass Method
This is the method professional framers and DIYers rely on most: mark all four faces, cut as deep as the saw allows, then flip the board and finish from the opposite side.
- Mark all four faces: Set a speed square against one face and draw a line across it. Continue the line around all four sides of the 4×4 with a pencil so the marks meet exactly — this is what keeps the two passes aligned.
- Score the cut line with masking tape (optional): Apply a strip of masking tape over the marked line before cutting. It bites down the wood fibers and reduces splintering, especially on cedar or pressure-treated stock.
- Secure the 4×4: Clamp the board to sawhorses with the cut line clear of any support, so the blade won’t bind or the offcut won’t pinch the blade as it falls.
- Set blade depth: Adjust the depth so the blade extends about 1/4 to 1/2 inch past the bottom of the board — deep enough to cut cleanly, not so deep that it’s exposed and dangerous.
- Make the first pass: Align the saw’s baseplate with the marked line and cut through the first face at a steady, even pace. Let the saw run at full speed before it contacts the wood.
- Flip the 4×4: Rotate the board 180 degrees so the uncut face is up, keeping the marked line aligned with where the first cut ended.
- Make the second pass: Line the blade up with the kerf (the slot) from the first cut and guide the saw through the remaining thickness. The two cuts should meet in the middle.
- Separate the pieces: If a thin strip of wood is still connecting the two halves, finish it with a handsaw rather than forcing the circular saw through — this is the most common point where kickback happens.
Best Circular Saw Blade Pick for 4×4 Lumber
DEWALT Circular Saw Blade, 7 1/4 Inch, 40 Tooth – $13.77
A 40-tooth carbide blade matches the clean, splinter-resistant cut this guide’s two-pass method depends on — especially on the second, flipped pass where alignment matters most.
- Best for: Clean crosscuts on framing lumber and 4×4 posts
- Why we picked it: Thin-kerf carbide teeth stay sharp through repeated two-pass cuts without bogging down the motor
- Main drawback: Not a specialty blade — swap to a higher tooth count for finish-grade cuts
Compare more 7 1/4-inch blade options
 Option 1 COMOWARE 40T Blade – $12.99
|
 Option 2 WORKPRO 40T Blade – $12.99
|
 Option 3 Revvstark 3-Pack Combo – $23.99
|
As an Amazon Associate we earn from qualifying purchases.
Avoiding Kickback and Splintering
Kickback happens most often at two moments: when the blade binds because the offcut pinches it, and when you force the saw through the last sliver of wood on the second pass instead of finishing it by hand. Both are avoidable with the same habits.
- Support both sides of the cut. If the offcut isn’t supported, its weight can pinch the blade the instant it separates.
- Let the blade reach full speed before it touches the wood, and never twist the saw once it’s in the cut.
- Keep the baseplate flat against the wood the entire length of the cut — lifting it even slightly can bind the blade.
- Finish the last inch by hand once the two passes meet, rather than forcing the circular saw through a thin, unsupported strip.
- Use a sharp blade. A dull blade needs more forward pressure to cut, which is exactly the condition that causes kickback.
“The moment you feel the saw start to bind or slow down mid-cut, back it out rather than pushing through — that hesitation is the saw telling you the offcut is pinching the blade.”
Alternative: Four-Side Rotation Method
Instead of flipping the 4×4 once (two-pass method), some carpenters rotate it 90 degrees after each cut and work around all four faces. This spreads the blade depth more evenly and can leave a straighter finished edge on rough-sawn or slightly warped stock.
- Mark the cut line on all four faces as in the two-pass method.
- Cut the first face to maximum blade depth.
- Rotate the 4×4 90 degrees, using the notch from the first cut to help align the blade with the second face.
- Repeat on the third and fourth faces until the piece separates.
This method takes longer than the two-pass flip, but it’s worth using on stock that isn’t perfectly square, since it keeps the blade closer to the true center of the cut on every pass.
Common Mistakes When Cutting a 4×4
- Trying to cut through in one pass. Forcing a 7 1/4-inch blade past its 2 1/2-inch depth stalls the motor and is a common cause of kickback.
- Not aligning the marks on all four faces. If the lines don’t meet exactly, the two cuts won’t line up and you’ll end up with a visible step or an angled cut.
- Skipping the clamp. A 4×4 that shifts mid-cut is the fastest way to bind the blade.
- Using a worn or wrong-tooth-count blade. A dull or low-tooth-count blade tears the exit side instead of cutting it cleanly.
Frequently Asked Questions
Can you cut a 4×4 with a regular circular saw?
Yes. A standard 7 1/4-inch circular saw can cut a 4×4, but it can’t do it in a single pass because its maximum depth of cut (about 2 1/2 inches) is less than the 4×4’s actual 3 1/2-inch thickness. Cut partway through from one face, flip the board, and finish the cut from the opposite face using the same marked line.
What blade do I need to cut a 4×4 with a circular saw?
A 7 1/4-inch carbide-tipped blade with 24 to 40 teeth works for most 4×4 lumber. Fewer teeth (24T) cut faster through pressure-treated framing stock; more teeth (40T) leave a cleaner, less splintered edge, which matters more on cedar or a post that will stay visible.
Can you cut a 4×4 in one pass?
No, not with a standard 7 1/4-inch circular saw. The blade’s maximum depth of cut is about 2 1/2 inches, roughly an inch short of a 4×4’s 3 1/2-inch thickness. An 8 1/4-inch worm-drive saw gets closer but still typically can’t complete the cut in a single pass without flipping the board.
How do you keep a 4×4 cut straight?
Mark the cut line on all four faces using a speed square before you cut, and clamp the 4×4 so it can’t shift. Keep the saw’s baseplate flat against the wood through the entire cut, and let the blade do the work instead of forcing it — pushing too hard is what pulls a cut off-line.
Conclusion
A 7 1/4-inch circular saw handles a 4×4 easily once you plan for the depth-of-cut gap: mark all four faces, cut as deep as the saw allows, then flip and finish from the opposite side. Support both ends of the board, keep the blade sharp, and finish any remaining sliver by hand instead of forcing the saw through it. With those habits, you’ll get a straight, clean cut without the stalling or kickback that catches people who try to power through in a single pass.
