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Room estimate
Measurements and quantities
Carpet calculator for rooms, underlay and tiles
Work out a rectangular room estimate, then have the cutting sizes checked before ordering.
Use the carpet calculator to separate the floor area from the carpet you may buy off a roll. Square tile and underlay estimates use the same room measurements, with optional prices entered from your own quote.
- Room units
- Metres or feet, converted to square metres
- Scope
- Rectangular rooms and square tiles
- Prices
- Your quoted material prices only
- Before buying
- Warehouse quantity and cutting-plan check
How many square metres of carpet do I need?
For a rectangular room, multiply the measured length by its width to find the floor area. Measure the widest points, including recesses and doorways that will be carpeted. That floor area is useful, but it is not automatically the area of carpet you buy. Carpet comes from a fixed-width roll, and the cut must cover the room in the right direction. The calculator separates floor area from a possible single-piece roll purchase so those two quantities are not mistaken for one another.
A carpet calculator is a starting point, not a cutting plan
Enter the actual roll width you are considering. The tool checks both rectangular orientations and uses the shorter single-piece cut where one fits. In practice, pile direction, a pattern repeat or the way adjoining rooms connect can require a different orientation. If neither room dimension fits within the roll width, the tool asks for a cutting plan rather than guessing a join. Irregular rooms, bays and staircases also need their shapes considered separately. Have the warehouse check the quantities before ordering or cutting.
Use the underlay calculator for the floor beneath
The underlay area is the rectangular floor area, not the roll-width carpet purchase. This distinction matters in a narrow room where buying full-width carpet leaves an offcut. Enter an underlay price per square metre from your quote if you want an underlay material estimate. Actual underlay may be supplied in pack quantities, so the final order can differ from the bare area. Ask about product suitability, pack coverage and what the fitted quote includes rather than assuming every underlay is interchangeable.
How many carpet tiles do I need?
For square carpet tiles, enter the tile side length and the number in the actual box. The calculator counts whole tile rows in each direction, then rounds up to whole boxes. It does not assume that cut pieces from one wall can be reused at another. That gives a clear rectangular layout estimate; pattern direction, awkward boundaries and spares can change the order. For a 12 by 12 foot room with example 50cm tiles, the calculation is eight rows by eight rows: 64 tiles before box rounding.
There is no universal number of carpet tiles in a box
Read the pack information for the product you are buying and replace the example box quantity in the tool. Tile size and pack quantity both affect the number of boxes. If your tile is rectangular, do not use the square-tile calculation for a final order. A different laying pattern or staggered arrangement also needs a separate layout check. The estimate describes a straight square grid, not every way carpet tiles can be installed. Keep the product details with your measurements when requesting a price.
Estimate material costs using your own quoted prices
The carpet calculator UK figures are in pounds and square metres. If your room measurements are in feet, select feet and the tool converts them using 0.3048 metres per foot. Carpet and underlay prices must be entered per square metre; the carpet tile cost calculator uses a price per tile and the box-rounded quantity. Blank price fields stay blank in the results. The figures are material estimates only, excluding fitting, preparation, accessories, delivery and any extra spare material. Compare like-for-like quote lines instead of treating the result as a fitted price.
Measure once more before making the purchase
Check that the dimensions refer to the room floor, not furniture or an estate-agent plan. Add the doorway recess into the measurement where carpet needs to reach it, and record any alcove or cupboard separately on a sketch. Do not add a blanket waste percentage and assume it solves all cutting problems: a pattern repeat or a wide room needs a specific plan. Take the sketch and your calculated figures to the warehouse so the team can work out quantities from the room measurements before a piece is cut.
From quantities to a warehouse quote
Kent Carpet Warehouse stocks carpet and underlay at its Maidstone and Gillingham warehouses, open to public and trade. Send the room sizes together with the roll or tile details you have used. Supply-only buying is welcome, including when your own fitter supplies the cutting sizes. If you want fitting arranged, trusted, fully vetted local fitters are used and onsite measuring is available in most Kent areas. Use the estimate to organise the conversation, then confirm the material, quantity and separate quote lines for your actual rooms.
Measurements and the next step
Have the quantities checked and priced
Send your room sizes and product details so the warehouse team can check quantities and give an itemised quote.
Carpet calculator questions
- Is floor area the same as carpet purchase area?
- Not always. A fixed-width roll may leave unused width, and patterns or pile direction can alter the required cut. The tool shows floor area and a single-piece roll estimate separately.
- How many carpet tiles cover a 12 by 12 foot room?
- With example 50cm square tiles in straight rows, a 12 by 12 foot room needs eight rows by eight rows, or 64 tiles before box rounding. The actual tile size, layout and pack quantity must be checked.
- How many carpet tiles are in a box?
- The number depends on the product. Enter the quantity printed on the pack; the example in the calculator is not a stock or pack-size promise.
- Does the underlay cost calculator include fitting?
- No. It multiplies rectangular floor area by the underlay price per square metre you enter. Pack rounding, fitting, accessories, preparation and delivery are separate.
- Can this calculator measure my stairs?
- No. Stairs, winders and landings need a cutting plan that accounts for their shapes and pile direction. Ask about onsite measuring, available in most Kent areas.