Area Calculator (Every Shape, Every Unit)
CivilSite.in — tools for Indian construction
Updated
Pick a shape, enter the dimensions in feet or metres, and get the area — plus the same area in square feet, square metres, gaj, cent and acre. The formulas are exact geometry, so the answer is precise, not indicative.
Area Calculator — any shape, any unit
Rectangle, circle, triangle, trapezium and more — with sq ft, sq m, gaj and acre
Rectangle area
300 ft²
L × W · measured in ft
Square feet
300 sq ft
Square metre
27.87 m²
Square yard (gaj)
33.33 gaj
Square inch
43,200 sq in
The same area in every unit
sq ft
300
sq m
27.87
sq yd / gaj
33.33
sq in
43,200
sq cm
2,78,709.1
cent
0.689
acre
0.0069
hectare
0.0028
Exact geometry, not an estimate. Use it for plot and room areas, plaster and paint quantities (area × coats), tiling, and land in gaj or cent. For an L-shaped room, split it into rectangles and add the areas.
Area formulas used
| Shape | Area formula |
|---|---|
| Rectangle | Length × Width |
| Square | side² |
| Triangle | ½ × base × height |
| Circle | π × radius² |
| Trapezium | ½ × (a + b) × height |
| Parallelogram | base × height |
| Rhombus | ½ × diagonal₁ × diagonal₂ |
| Ellipse | π × semi-axis a × semi-axis b |
Where an area calculator helps on a build
- Plot and room area — for planning, FSI and comparing listings.
- Plaster and paint — quantity scales with area × number of coats (paint thumb rule: ~0.18 L/sq ft for two coats).
- Flooring and tiles — tile quantity is roughly floor area × 1.3 for skirting and wastage (tile costs).
- Land in local units — convert to gaj, cent, guntha or bigha.
L-shaped or irregular rooms
Real rooms are rarely a single clean shape. Split an L-shape or an irregular plan into rectangles (and triangles), compute each, and add them up — the calculator handles each piece, and the total is the sum.
Worked example
A rectangular plot 40 ft × 30 ft has an area of 40 × 30 = 1,200 sq ft, which is about 111.48 m², 133.33 gaj and 0.0275 acre.
Frequently asked questions
How do I calculate the area of a room? For a rectangular room, multiply length by width. For an L-shape, split it into rectangles, find each area, and add them. Use the calculator above and pick your unit.
How do I convert square feet to square metres? 1 sq ft = 0.092903 m², so divide square feet by 10.7639 to get square metres — the calculator shows both at once.
What is the area of a circle? π × radius². For a radius of 5 ft, the area is about 78.54 sq ft.
How many square feet is 1 gaj? 1 gaj (square yard) is 9 square feet. The calculator converts area into gaj automatically.
Related
CivilSite Editorial Team✓ Engineer reviewed
Written and reviewed by practising civil engineers with 10+ years of Indian residential construction experience.