Free Online Calculators
Tiles, adhesive & grout quantity calculator
Whether you're tiling a bathroom floor, a kitchen backsplash, or an entire living room, knowing exactly how many tiles you need before you buy saves time, money, and frustration. The basic formula is simple: divide the total area of the room by the area of one tile. But real projects are rarely that clean. Doorways, odd corners, and cutting waste all add up fast, which is why a dedicated tile calculator makes a real difference.
A good rule of thumb is to add at least 10% waste for straight lay patterns, 15% for offset (brick bond) patterns, and up to 20% for diagonal patterns. Diagonal layouts generate more offcuts because tiles need to be cut at 45-degree angles along every wall edge. For example, if your room measures 4m × 5m (20 m²) and you're using a diagonal pattern, you'd want to purchase enough tiles to cover roughly 24 m² to account for cutting loss and breakage.
Most DIYers focus only on tile count and forget about adhesive and grout until they're standing in the hardware store. Tile adhesive coverage typically runs between 4–6 kg per square metre depending on the tile size and substrate. Larger format tiles (600×600mm or bigger) often need a thicker bed of adhesive, so consumption edges toward the higher end. For our 20 m² example using standard coverage of 5 kg/m², you'd need approximately 100 kg of adhesive — that's about five 20 kg bags.
Grout quantity depends on tile size, grout joint width, and tile thickness. Smaller tiles with narrow joints use less grout per square metre than large tiles with wide joints. A 300×300mm tile with a 3mm joint on a 20 m² floor typically requires around 3–4 kg of grout. Getting this number right means fewer emergency trips back to the store mid-project, especially if you're using a colour-matched grout that may not be easy to find in a hurry.
At simple-calculator.online, the tile calculator handles all of these variables automatically — just enter your room dimensions, tile size, preferred laying pattern, and joint width, and it instantly shows you tile count, adhesive weight, and grout quantity in one place.
Straight lay is the most material-efficient pattern and the easiest to install — tiles align in a simple grid. Offset (or brick bond) shifts each row by half a tile, creating a classic staggered look popular in kitchens and hallways. Diagonal patterns rotate the grid 45 degrees, adding visual interest but also adding complexity and waste. For awkward rooms with multiple recesses or obstacles, straight lay is the safest choice to minimise offcuts and keep costs predictable.
Add 10% for straight patterns, 15% for offset, and 20% for diagonal. If your tiles are from a single batch, buying a few extra is always smart since dye lots can vary between production runs.
Multiply your floor area in m² by the adhesive coverage rate shown on the product bag (typically 4–6 kg/m²). Always check the manufacturer's spec sheet for the exact product you're using.
Yes. Simply measure the wall area (width × height) and subtract any openings like windows or doors. The same waste percentages and material calculations apply for wall installations.