Square Footage Calculator - Calculatrice en ligne gratuite

Square footage is the most common unit for measuring property in India - flats are advertised in 'sq ft', rentals quoted per sq ft, property tax assessed on sq ft, and renovation costs quoted per sq ft. Yet the term 'sq ft' itself can mean different things depending on context: carpet area (the usable space inside walls), built-up area (including walls and balcony), or super built-up area (adding a share of common amenities like lobby, staircase, and clubhouse). Understanding which 'sq ft' is being quoted matters enormously when comparing flats, paying property tax, or estimating renovation costs.

RERA (Real Estate Regulatory Authority) regulations, in force since 2017, now require builders to advertise and sell on carpet area basis - the actual usable space. The shift from super built-up to carpet pricing has changed how buyers compare flats. A 'super built-up' 1,200 sq ft flat from before RERA might have only 800 sq ft carpet area; the same flat under RERA must be quoted at the carpet number. This calculator helps you measure rooms accurately and convert between Indian units like sq ft, sq m, sq yd (gaj), ground (Tamil Nadu, 2,400 sq ft), guntha (Maharashtra, 1,089 sq ft), bigha (varies by state) and acre (43,560 sq ft).

Rectangle: area = length × width. The most common shape for rooms, flats, plots and parcels. For non-rectangular spaces (L-shape, T-shape), divide into rectangles and sum. Circle: area = π × radius². Useful for circular patios, gazebos, water tanks. Triangle: ½ × base × height (where height is perpendicular distance from base to apex). Useful for irregular plot corners and gable end walls. Trapezoid: ½ × (parallel side 1 + parallel side 2) × perpendicular height. Common for irregular plots with two parallel boundaries.

Unit conversions used in India: 1 sq m = 10.764 sq ft. 1 sq yard (gaj) = 9 sq ft. 1 ground (Tamil Nadu/Andhra) = 2,400 sq ft. 1 guntha (Maharashtra/Karnataka) = 1,089 sq ft = 121 sq yards. 1 cent (Kerala/Tamil Nadu) = 435.6 sq ft. 1 bigha varies - 14,400 sq ft in West Bengal, 27,225 sq ft in UP, etc. 1 acre = 43,560 sq ft. 1 hectare = 107,639 sq ft = 2.47 acres. Always confirm regional unit before transactions.

Carpet vs built-up vs super built-up: Carpet area = usable area inside the apartment walls (excluding balcony, walls, common). Built-up area = carpet + balcony + walls = ~1.10-1.15× carpet. Super built-up = built-up + proportional share of lobbies, staircases, lifts, clubhouse, terraces = ~1.25-1.40× carpet (depending on amenities). RERA now mandates sales on carpet basis; older listings still use super built-up which can be 30-40% larger.