Work out a room or plot's area from its dimensions, convert between Indian land units including a state-aware Bigha converter, or turn a flat's Carpet Area into its Super Built-up Area.
Key Takeaways
- Bigha is not one fixed size in India — a Bigha in West Bengal (about 14,400 sq ft) is roughly half the size of a Bigha in Uttar Pradesh (about 27,225 sq ft), and figures can vary further by district. Always verify locally before treating a Bigha figure as exact.
- Square Feet, Acre, Hectare, Cent, Guntha, Ground, Kanal, and Marla are standardised and safe to convert with a fixed factor anywhere in India, unlike Bigha, Katha, and Biswa.
- Carpet Area is always smaller than Super Built-up Area, often by 20–40%, because Super Built-up adds wall thickness and a share of common areas like lobbies and stairwells — the price-per-square-foot quoted by a builder usually applies to Super Built-up, not Carpet Area.
What This Square Footage Calculator Does
This calculator handles the area questions that come up constantly in Indian real estate. Area from Dimensions takes a room or plot's length and breadth and gives you the square footage instantly. Unit Converter takes any area and shows it in every standardised Indian and metric unit at once — square feet, square metres, square yards (gaj), acres, hectares, cents, gunthas, grounds, kanals, and marlas. State-wise Bigha handles the trickiest unit in Indian land measurement: Bigha varies so much by state that a single national conversion would be actively misleading, so this mode is state-aware. Carpet to Super Built-up solves the classic apartment-buying confusion between the space you actually get and the larger number builders often quote, using a loading percentage.
Everything runs entirely in your browser. No dimension, area, or state you enter is sent to a server, logged, or stored anywhere — close the tab and it's gone. There's no signup, no email wall, and no ads inside the calculator itself. For any figure that will go into a legal document or a real transaction, cross-check it against your sale deed or local land revenue records — the disclaimer above the results explains why, especially for Bigha.
How to Use This Square Footage Calculator
1. Area from Dimensions
- Enter Length and Breadth in feet or metres.
- Read the area in square feet, plus every other unit below it.
2. Unit Converter
- Enter a Value and pick the From Unit.
- See it converted to every other standard unit at once.
3. State-wise Bigha
- Enter the area in Square Feet.
- Pick your State.
- See the Bigha equivalent for that state specifically.
4. Carpet ⇆ Super Built-up
- Choose whether you know the Carpet Area or the Super Built-up Area.
- Enter that value and the Loading Percentage.
- See the other figure calculated instantly.
The Formulas, Explained
Area from Dimensions: Area = Length × Breadth.
Unit Conversion: every unit here is converted via its fixed square-feet equivalent: Result in Target Unit = (Value × Sq Ft per Source Unit) ÷ Sq Ft per Target Unit.
Carpet to Super Built-up: Super Built-up Area = Carpet Area × (1 + Loading% / 100). Reversed: Carpet Area = Super Built-up Area ÷ (1 + Loading% / 100).
Worked example (Area from Dimensions): Length 40 ft, Breadth 30 ft.
- Area = 40 × 30 = 1,200 sq ft
- In square metres: 1,200 ÷ 10.7639 ≈ 111.5 sq m
- In square yards (gaj): 1,200 ÷ 9 = 133.3 sq yd
- In acres: 1,200 ÷ 43,560 ≈ 0.0275 acre
Worked example (Carpet to Super Built-up): Carpet Area 800 sq ft, Loading 30%.
- Super Built-up = 800 × (1 + 0.30) = 1,040 sq ft
- Carpet Area Efficiency = 800 / 1,040 × 100 ≈ 76.9%
Indian Land Unit Reference Table
Fixed conversion factors for the standardised units (safe to use anywhere in India), followed by commonly cited Bigha values by state (verify locally before relying on these).
| Unit | Equal To |
|---|---|
| 1 Square Metre | 10.7639 sq ft |
| 1 Square Yard (Gaj) | 9 sq ft |
| 1 Cent | 435.6 sq ft |
| 1 Guntha | 1,089 sq ft |
| 1 Ground | 2,400 sq ft |
| 1 Marla | 272.25 sq ft |
| 1 Kanal (20 Marla) | 5,445 sq ft |
| 1 Acre | 43,560 sq ft |
| 1 Hectare | 1,07,639 sq ft |
| State | 1 Bigha (approx.) |
|---|---|
| West Bengal | 14,400 sq ft |
| Gujarat (Vigha) | 17,424 sq ft |
| Uttarakhand | 6,804 sq ft |
| Himachal Pradesh | ~6,800 sq ft |
| Bihar | 27,220 sq ft |
| Uttar Pradesh | 27,225 sq ft |
| Rajasthan | ~27,225 sq ft |
| Madhya Pradesh | ~27,225 sq ft |
Quick Definitions
Carpet Area is the actual usable floor area inside an apartment's walls — the space you could literally lay a carpet over. Super Built-up Area (also called saleable area) adds the thickness of the apartment's own walls plus a proportional share of common areas like lobbies, staircases, and lift shafts, which is why it's always a larger number than Carpet Area for the same flat.
Frequently Asked Questions
Before India adopted the metric system, each princely state and revenue district defined its own local land units, and those historical definitions survived in land records even after independence. Bigha, Katha, and Biswa were never nationally standardised the way Acre, Hectare, or Guntha eventually were.
Carpet Area is the actual usable floor space inside the walls. Built-up Area adds the thickness of the flat's own walls on top of that. Super Built-up Area (or saleable area) adds a further proportional share of common building areas like corridors, lobbies, and staircases — it's usually the number a builder's quoted price-per-square-foot is based on.
RERA (the Real Estate Regulatory Authority) requires builders to disclose Carpet Area clearly in the sale agreement so buyers can see the true usable space, but it doesn't fix a maximum loading percentage — that varies by project and building design. Always check the RERA filing for the project's exact Carpet Area figure.
Your sale deed and the local land revenue record (Bhulekh or the equivalent state land records portal) are the authoritative sources for a specific plot. A general calculator like this one is for quick estimates and comparisons, not a substitute for those documents in an actual transaction.
No, these are standardised: 1 Guntha is 1,089 sq ft and 1 Cent is 435.6 sq ft nationwide, unlike Bigha. Guntha is used mainly in Maharashtra and Karnataka, and Cent mainly in Kerala, Tamil Nadu, and Andhra Pradesh/Telangana, but the conversion factor itself doesn't change by region.
No. Every calculation runs locally in your browser using JavaScript; nothing you enter is transmitted to any server, logged, or saved once you close or refresh the page.