Blue Wool Slab is the half-height slab form of Blue Wool, one of sixteen wool slab colors that Minecraft added in Java Edition 26.3 after announcing wool slabs at Minecraft Live in May 2026. Three Blue Wool blocks placed in a single crafting row yield six Blue Wool Slabs, and any wool slab accepts a matching dye to change color, exactly like wool. Breaking Blue Wool Slab works with any tool, though Shears are the fastest; hardness is 0.8, and blast resistance (how well the block withstands TNT and creeper explosions) reaches 0.8 in Java Edition but only 0.16 in Bedrock Edition. Blue Wool Slab is a renewable resource (wool from sheep can be dyed and sheared endlessly), stacks to 64 slabs of one color, burns in fire, and disappears in lava.

Blue Wool Slab gives builders smooth blue flooring, accent stripes, and gentle half-step stairs — wool slabs placed on the ground occupy the bottom half of a block, wool slabs placed against the underside of a block hang in the top half, and two matching wool slabs merge into one full double slab. The wool family also hides a stealth perk: Blue Wool Slab blocks vibrations, so a Sculk Sensor cannot detect movement behind a placed slab, and the Warden loses those signals as well. Three Blue Wool Slabs in a crafting row produce one Blue Cushion, a seat players can sit on. In Java Edition Blue Wool Slab even works as furnace fuel at four slabs per smelted item, while fire and lava remain the main enemies of blue wool builds.