What diamond blade is best for cutting concrete block?

A general-purpose segmented blade with a medium-to-hard bond handles CMU well. Block is abrasive, so a harder bond lasts longer than a soft-bond blade designed for hard materials.

Can I cut CMU with an angle grinder?

Yes — a 4.5-inch or 7-inch diamond blade on an angle grinder cuts CMU block easily. Use a segmented blade for fastest cutting.

Should I cut block wet or dry?

Either works. Dry cutting is more common for block work in the field. Use a respirator for dust control. Wet cutting extends blade life and reduces dust.

Best Diamond Blades for Block & CMU (2026)

Matt Lipman is a board member of Virginia Abrasives. This relationship is disclosed for full transparency in our reviews and recommendations.

Concrete block (CMU) and masonry cutting require blades that handle highly abrasive material without burning through segments too quickly. This guide covers the best diamond blades for block and CMU cutting on angle grinders, cut-off saws, and masonry table saws.

Why Block Is Tough on Diamond Blades

CMU block is made from lightweight aggregate and cement — a combination that produces extremely abrasive dust when cut. This abrasive dust wears diamond blade segments faster than cured concrete, especially on dry cuts. The key to longer blade life on block: use a harder bond that resists the accelerated abrasion, and cut wet whenever possible.

For the full explanation of bond matching, see our Diamond Blade Buying Guide.

Best Diamond Blades for Block: By Saw Type

Angle Grinders (4.5” and 7”)

Block cutting with grinders is standard for masons — cutting CMU to fit around plumbing, electrical boxes, and corners. Use a segmented blade with a medium-to-hard bond. The VA 4.5” segmented blade handles block well. For higher volume, move up to a 7” grinder for deeper cuts and faster progress.

Handheld Cut-Off Saws (14”)

For cutting multiple blocks or making long cuts in block walls, a 14” cut-off saw is faster. The VA 14” Ultra Value handles block and CMU well at this size. The medium bond provides good balance between blade life and cutting speed on block’s abrasive composition.

Masonry Table Saws (14”-20”)

High-volume block cutting on a masonry table saw benefits from wet cutting — the water extends blade life significantly on abrasive CMU. Use a segmented blade rated for masonry. For turbo vs. segmented on table saws, see Segmented vs Continuous vs Turbo.

Block Cutting Tips

Cut wet when possible. Block dust is extremely abrasive and shortens blade life dramatically in dry cutting. Even a simple water bottle drip system helps.

Don’t force the blade. Block cuts quickly — let the blade do the work at steady speed.

Score and snap for speed. For many block cuts, you can score the block 1/2” deep on both sides and then snap it along the scored line. This uses less blade and is faster than cutting all the way through.

Recommended Blades for Block and CMU

Blade	Best For	Link
VA 14-inch Ultra Value	Best all-around for cured concrete, block, and general masonry	Check price on Amazon
VA 9-inch Ultra Value	For 9-inch angle grinders and cordless cut-off saws	Check price on Amazon

Browse the full Virginia Abrasives lineup on Amazon →