Grout Calculator

Grout volume (cu in per sq ft) = 144 × joint width × joint depth × (tile length + tile width) ÷ (tile length × tile width). Multiply by your total square footage, convert to cubic feet, then multiply by grout density to get pounds needed.

Joint depth is usually the same as your tile's thickness, since grout fills the joint down to the substrate — a standard ceramic or porcelain tile is often 1/4" to 3/8" thick, but check your specific tile.

Smaller tiles have far more joint length per square foot than larger tiles, so they need significantly more grout for the same joint width and area — a wall of 4x4 tiles can need 5-6× the grout of the same wall in 12x12 tiles.

A lot — grout volume scales directly with joint width, so widening your joints from 1/8" to 3/8" roughly triples the grout needed for the same tile and area.

Yes — add 5-10% for mixing residue, spillage, cleanup waste, and future repairs, which this calculator already includes by default.