These free room calculators work out floor area, room volume, rug and curtain sizes, blind measurements, TV viewing distance, table size, worktop lengths and moving boxes for UK and EU homes.
Quick answer: Pick the job, measure the room in metres or feet and enter the numbers. Each calculator shows the result, the formula and a breakdown, and flags common mistakes such as forgetting a wall border for a rug or extra fabric for curtain fullness.
How Do You Measure a Room Accurately?
Measure each wall at floor level to the nearest centimetre and split L shaped or angled rooms into rectangles and triangles. The irregular room area calculator adds the pieces and subtracts chimney breasts or other cut outs.
Why Does Curtain Fabric Need More Width Than the Window?
Curtain headings gather the fabric, so you usually need 1.5 to 2.5 times the pole length depending on the heading. The curtain calculators include this fullness so the curtains close properly.
Which Room Calculators Do You Need?
Measure the room first: length, width and ceiling height, plus any alcoves or bay windows. Then pick the room calculator that matches the job, whether that is buying a rug, ordering blinds, fitting a worktop or planning a move.
| Tool | What it works out |
|---|---|
| Square Metre Calculator | Works out square metres for rectangles, circles and triangles, with extra and cost. |
| Room Volume Calculator | Works out a room's volume in cubic metres, cubic feet and litres, plus airflow needed. |
| Irregular Room Area Calculator | Works out the floor area of L-shaped and irregular rooms by adding sections and subtracting cut-outs. |
| Rug Size Calculator | Works out the right rug size for a living room, dining room or bedroom. |
| Curtain Size Calculator | Works out pole length, curtain drop, curtain width and the nearest UK ready made size. |
| Curtain Fabric Calculator | Works out how many metres of curtain fabric and lining to buy, including pattern repeat. |
| Blind Size Calculator | Works out the blind width and drop to order for inside or outside recess fitting. |
| TV Size and Viewing Distance Calculator | Works out the best TV size for your seat, or the best seat for your TV. |
| Dining Table Size Calculator | Works out the table size your diners need and the largest table your room fits. |
| Kitchen Worktop Calculator | Works out worktop area, how many standard lengths to buy, joints and upstand length. |
| Moving Box Calculator | Estimates how many small, medium and large moving boxes and tape rolls you need. |
| Picture Hanging Height Calculator | Works out where to put the nail or hooks so a picture hangs at eye level. |
How Our Room Calculators Work
Our room calculators round to the sizes you can actually buy. A curtain answer is matched to UK ready made widths, a worktop answer to standard lengths and a blind answer to the recess deduction most makers ask for.
Measurements follow metric definitions set out in the Weights and Measures Act 1985. Spacing guides, such as the gap around a dining table, are common industry rules of thumb and are labelled as examples you can change.
Tips for Accurate Results With Our Room Calculators
- Measure each wall at floor height and at waist height, and use the larger figure if the room is not square.
- Split L-shaped rooms into rectangles, work out each one, then add them together.
- Write measurements down in one unit. Our room calculators accept metres or feet, but do not mix them.
- Measure window recesses at the top, middle and bottom, and order blinds for the narrowest point.
- Allow walking space: about 90 cm around a dining table and 60 to 90 cm in front of a sofa.
Common Mistakes to Avoid
- Forgetting skirting boards, radiators and alcoves when measuring for rugs and furniture.
- Rounding measurements down. Round up to the nearest centimetre before ordering.
- Ordering curtains to the window width only. Curtains need extra width to gather properly.
- Measuring a TV by its frame instead of the diagonal screen size.
Room Calculators FAQs
Do these calculators work in feet and inches?
Yes. Switch to imperial at the top of each calculator and lengths and areas display in feet and square feet, while the working still shows the metric figures.
How big should a rug be?
A living room rug usually sits about 45 cm in from the walls, and a dining rug should extend about 60 cm beyond the table on every side so chairs stay on it. The rug size calculator applies both rules.
Can I plan a house move with these tools?
Yes. The moving box calculator estimates small, medium and large boxes and tape from the number of rooms, with editable defaults you can adjust for how much you own.
For flooring the same room, use the laminate flooring calculator or the paint calculator for the walls.