Room Materials Calculator
Measure a room once and estimate paint, primer, floor or wall tile, flooring packs, wallpaper rolls, and baseboards using your product labels.
Measure a rectangular room once to estimate paint, primer, floor and wall tile, packaged flooring, wallpaper, and baseboards. Enter the coverage and package sizes from the products you plan to use. The calculator shows its area, allowance, and package-rounding steps so you can review the estimate before shopping.
How to Use Room Materials Calculator
Measure the room
Enter the room length, width, and wall height. Switch between metric and US customary units; the underlying room dimensions stay the same.
Add doors and windows
Add each opening to its wall and enter its measured size and position. Openings reduce painted and tiled wall areas. Wallpaper is estimated as full-height strips, so openings are not subtracted from its strip count.
Choose the surfaces and finishes
Select a finish for each wall, then choose a floor finish and whether to paint the ceiling, prime painted surfaces, or estimate baseboards. For a tiled lower wall with paint above, enter the tile band height.
Enter package coverage and allowances
Copy coverage, container or pack size, and pieces per box from your chosen product label. Set a project allowance that suits your layout; the tool does not assume one waste rate fits every installation.
Review the shopping estimate
The result separates calculated material need from whole packages to buy. Add optional prices to see a priced subtotal or complete total in the selected currency. Currency selection changes display only and does not convert exchange rates.
Calculator Features
Measure once
Reuse room dimensions for wall, ceiling, and floor estimates.
Paint and primer
Estimate litres or US gallons from surface area, coats, label coverage, and a user-set reserve.
Tile and flooring
Estimate tiles, boxes, and flooring packs from face size or package coverage.
Wallpaper and trim
Estimate full-height wallpaper strips with straight-repeat allowance and baseboard stock lengths.
Complete Function List
- Metric and US customary room dimensions
- Measured openings assigned to individual walls
- Paint and primer coverage from product labels
- Separate floor and wall tile estimates
- Flooring package coverage and allowance
- Wallpaper full-height strips and straight pattern repeat
- Baseboard length with floor-touching door deductions
- Optional product prices and purchase rounding
- Local browser calculation without live price data
Common Calculations & Examples
Example 1: Estimate paint and floor tile for a 4 m by 3 m room
Problem: A room is 4 m long, 3 m wide, and 2.5 m high. It has a 1 m by 2 m door and a 1.5 m by 1 m window. Estimate wall paint at two coats and floor tile using editable example product inputs.
Steps:
- The gross wall area is 2 × (4 + 3) × 2.5 = 35 m². Subtract 2 m² for the door and 1.5 m² for the window to get 31.5 m² of net wall area.
- At two coats and an entered coverage of 10 m² per litre per coat, the theoretical paint requirement is 31.5 × 2 ÷ 10 = 6.3 L before any reserve.
- The 12 m² floor with 0.3 m by 0.3 m tiles contains 12 ÷ 0.09 = 133.34 tile face areas. With an entered 10% allowance, round up to 147 tiles. At 12 tiles per box, buy 13 boxes.
Explanation: The coverage, reserve, tile dimensions, and box count are sample inputs to demonstrate the formulas. Enter specifications from the product you intend to buy. The tile quantity uses a face-area estimate and is not a placement or cut layout.