What is the difference between feet and square feet?
Feet measure one-dimensional length. Square feet measure two-dimensional area. A room 12 ft long and 10 ft wide has an area of 120 sq ft, not 22 ft or 120 ft.
Area, Rooms & Plots calculator
Area Calculator
Calculate room, plot, circle, triangle, trapezoid, parallelogram, or multiple-room area; convert common square units; and estimate cost by area.
Interactive calculator
Measure area, understand it, then choose the next estimate
Choose one shape or enter a known area. Results show square feet and square metres together, with optional cost and practical use warnings.
What to do next
Continue your decision
Formula, example, assumptions, and FAQs — open any section for the detail.
Formula
Rectangle, room, or plot
Area = length × width × quantityThe calculator converts both lengths to metres before multiplying. Use this for a rectangular floor, roof face, or plot boundary only when the entered dimensions describe that same surface.
Circle and triangle
Circle = π × radius² · Triangle = base × perpendicular height ÷ 2 · Heron: √(s(s−a)(s−b)(s−c))For a diameter, radius is diameter ÷ 2. Heron formula is used only when all three sides form a valid triangle; s is half the perimeter.
Trapezoid and parallelogram
Trapezoid = (parallel side A + parallel side B) × height ÷ 2 · Parallelogram = base × heightHeight means perpendicular distance. A sloping side is not the height unless it is perpendicular to the base.
Multiple rooms and area conversion
Room total = sum of each length × width · sq ft = sq m × 10.7639104167 · sq yd = sq ft ÷ 9Each room row may use its own length unit. Acre uses 4,046.8564224 sq m and hectare uses 10,000 sq m.
Optional cost by area
Cost = area in selected price unit × price per sq ft, sq m, or sq ydThe result also normalizes the entered rate to cost per square foot, square metre, and square yard. It does not add wastage, tax, labour, delivery, or a supplier minimum.
Worked example
Example: two rooms and a flooring rate
A 12 ft × 10 ft room and a 12 ft × 8 ft room need the same flooring. The entered material rate is ₹150 per sq ft.
Calculation:Room areas are 120 sq ft and 96 sq ft. Total = 216 sq ft = about 20.07 sq m = 24 sq yd. Cost before wastage and other charges = 216 × ₹150.
Result:The combined floor area is 216 sq ft and the area-based cost is ₹32,400. Continue to Tile Calculator to add tile size, grout, wastage, and box rounding. Do not use this floor area as wall paint area.
Assumptions
- All dimensions for one shape use the selected length unit; multiple-room rows may each use their own unit.
- Rectangle and room measurements are taken at right angles.
- Triangle and quadrilateral heights are perpendicular to their base or parallel sides.
- Quantity represents identical shapes and must be a positive whole number.
- Multiple-room mode adds up to five rectangular floor areas and does not subtract columns, cupboards, shafts, or openings.
- Gaj is shown as square yard because that is a common property usage, but users should confirm the unit used in their document or market.
- Bigha and biswa are not converted because their values vary by state and region.
- The optional price is a direct rate per selected area unit and does not include currency conversion.
Common mistakes
- Confusing feet with square feet, or metres with square metres. Length and area are different measurements.
- Using floor area for wall paint. Paint normally needs wall and ceiling surface area after relevant deductions.
- Using area alone for concrete. Concrete needs thickness or depth because it is measured by volume.
- Forgetting tile, flooring, roofing, or fabric wastage for cuts, breakage, pattern, overlap, or spare material.
- Entering a circle diameter as radius, which makes the calculated area four times too large.
- Using a sloping triangle or trapezoid edge as the perpendicular height.
- Treating square yard, gaj, bigha, and biswa as universally interchangeable.
- Using a plot calculation as legal boundary proof instead of checking official records or a survey.
Accuracy notes
Geometry and unit conversions are deterministic, and calculations use unrounded values internally before display rounding. Real accuracy depends on measurement quality, right angles, perpendicular heights, whether the shape matches the actual boundary, and whether deductions or irregular sections are included. Material and cost planning may require product-specific wastage or contract rules.
Frequently asked questions
Can I use room floor area for paint?
Not for walls. Floor area can help with floor tiles or flooring. Wall paint needs wall length, wall height, openings, coats, and coverage; ceiling paint may use ceiling area separately.
Can I use area to estimate concrete?
Area is only the first part. Concrete is volume, so you also need slab thickness, footing depth, or another third dimension. Continue to Concrete Calculator after confirming the surface area and depth.
Is gaj the same as square yard?
In many Indian property contexts, gaj is used to mean square yard, so this calculator labels them together. Confirm the wording and convention used in your document, agreement, or local market.
Why are bigha and biswa not included?
Their values vary by state, district, and local convention. Treating either as one universal exact area would create false precision. Convert only after confirming the applicable official or local definition.
Does the plot result prove legal land area?
No. It is geometry from the numbers entered. Boundaries, irregular shapes, encroachments, document conventions, and survey methods can change a legal land measurement. Verify official records or use a qualified survey.
How should I price tiles, flooring, or rent by area?
Enter the quoted rate per sq ft, sq m, or sq yd. The calculator gives a direct area-based cost. Add wastage, boxes, labour, delivery, tax, minimum order, common-area loading, or other contract terms separately.
Can I use this area calculator outside India?
Yes. Length supports metric and imperial units, area supports sq mm through hectares and acres, and currency is editable. The ₹ and gaj examples are defaults, not restrictions.
This calculator provides a geometric area, unit conversion, and optional rate estimate only. It is not a legal land survey, boundary certification, property valuation, contractor quote, structural calculation, or material purchase guarantee. Verify important room, plot, construction, and land-record measurements with the relevant documents and qualified professional.Read the full disclaimer.