Room Measurement Calculator
🇮🇳 India version
Rooms in India are usually described in feet, and tiles are priced by the square foot or sold in boxes. This version opens in feet and square feet, deducts doors and windows from the wall area, adds up every room, and turns the surface you pick into boxes with a wastage allowance.
Use Room Measurement Calculator online
Room Measurement Calculator
Work out floor area, wall area, perimeter and volume for every room in a project, deduct doors and windows, and turn the totals into a materials order.
Feet-and-inches shorthand works: 12'6", 12 6 or 12-6.
Feet-and-inches shorthand works: 12'6", 12 6 or 12-6.
India rules and figures
- Room sizes and tile rates in India are generally quoted per square foot, which is why the starting unit is feet and not metres.
- A box starts at 20 sq ft with 10% wastage, example figures that you replace with the details printed on the carton.
- India’s standard GST rate is 18% for most goods, so type the price per box as shown on the bill.
- Large rupee amounts show the Indian grouping, so a figure above one lakh reads 1,00,000.
Sources: Income Tax Department: India tax authority (checked 2026-11-08)
How the Room Measurement Calculator works
A room here means a rectangle under a flat ceiling. Lengths convert to decimal feet, the floor and wall areas follow, and the Materials tab rounds the waste-adjusted area up to a whole number of boxes.
floor = L × W; skirting length = 2(L + W); wall = perimeter × H − openings; boxes = ceil(area × (1 + waste ÷ 100) ÷ sq ft per box)
- Before you change anything, the page shows two sample rooms in feet, with openings already entered, which you can overwrite or delete.
- Shorthand such as 12'6" is read as 12.5 ft. In metres mode only plain numbers are read.
- A box covers 20 sq ft and waste starts at 10%. Tiles laid straight might use 5%, and the preset for it is one click.
- The cost stays zero until you enter a price per box in rupees, and no GST is added.
How to use the Room Measurement Calculator
- Enter each room. Type length, width and ceiling height in feet for the hall, bedrooms and kitchen, adding rooms with Add room.
- Add doors and windows. Use + Door and + Window and set each size and count. Standard sizes start at 2.67 × 6.67 ft and 3 × 4 ft.
- Read the area totals. The Totals tab gives the floor, net and gross wall, volume and skirting length across all rooms.
- Work out the tile boxes. On Materials pick Floor, set the wastage and the sq ft in a box, then the price per box in rupees.
- Share the sheet. Copy summary or Export CSV records the areas for the mason or the shop.
Example: A 12 × 10 ft bedroom with tiles at 5% and 10% wastage
The bedroom has a 10 ft ceiling, one door of 3 × 6.67 ft and two windows of 4 × 5 ft. Its floor is 120 sq ft, the skirting length 44 ft and the volume 1,200 cu ft. Gross wall is 440 sq ft and net wall 379.99 sq ft. Tiles at 5% wastage need 126 sq ft, which is 7 boxes of 20 sq ft. At 10% it needs 132 sq ft, also 7 boxes.
When to use the Room Measurement Calculator
- Tiling a flat. Enter each room, choose floor, and read the number of boxes with a wastage allowance for cuts.
- Painting quotation. Use gross wall and ceiling area to check a painter’s quotation per square foot.
- False ceiling or paneling. Take the ceiling area, which equals the floor area, for a false ceiling or panel estimate.
- Air-conditioner sizing. Use the room volume in cubic feet alongside the floor area when comparing capacities.
What the Room Measurement Calculator does not do
- Switching units converts the typed sizes (rounded to 4 decimals), so flipping back and forth can leave tiny rounding differences. Metric and feet-and-inches shorthand cannot be mixed: inch shorthand is read only in feet mode.
- Rooms are rectangles with flat ceilings. For an L-shape, add two rooms; sloping ceilings need an average height.
- The Materials tab prices whole units only, so the cost is units times the price you enter, with no discounts, tax or delivery. Outside the US no starting price is filled in.
- Opening areas ignore frames and reveals, and every door or window you add uses a typed size, not a catalogue size.
- Measure real rooms at several points: the tool trusts the one number you type for each side.
When something else is a better fit
- When you are estimating paint and want coats, texture and colour change built in, use the Paint Calculator.
- When you need to convert measurements between feet, metres and inches, use the Unit Converter.
- When the room is irregular or you need a scaled drawing, use a floor-plan or CAD app, or a laser measure with a sketch.
Questions about the Room Measurement Calculator
How many tile boxes does a 12 by 10 foot room need?
7 boxes of 20 sq ft. The floor is 120 sq ft, which becomes 126 sq ft at 5% wastage and 132 sq ft at 10%.
Can I enter feet and inches?
Yes. Type 12'6", 12-6 or 12 6 for 12 ft 6 in, or decimal feet such as 12.5. Inches of 12 or more are rejected as invalid.
How is net wall calculated?
It is perimeter times height minus every door and window you entered. For this bedroom, 440 sq ft of gross wall less 60.01 sq ft of openings leaves 379.99 sq ft.
Does it include GST on the tiles?
No. It multiplies the price you type by the whole boxes. Enter the price per box as billed if you want GST included, since India’s standard rate is 18% on most goods.
Does it remember my rooms?
Yes, but only in this browser on this device. A removed room goes to Recently deleted, and Reset asks first and keeps the previous list as a saved version.