Property & Land Measurement

Land Area Calculator: Convert Bigha, Katha, Decimal, Acre & More

Bigha in West Bengal is not the same as Bigha in Uttar Pradesh or Rajasthan. Here's a state-by-state breakdown of India's land units, with the formulas you need before signing any property paper.

Updated July 2026 · 10 min read

Buying, selling or inheriting land in India almost always means running into a unit that does not appear on any standard measuring tape: Bigha, Katha, Decimal, Guntha, Cent. Unlike Acre or Hectare, these units were never standardised nationally, which means the same word can refer to a genuinely different area depending on which state's land records office issued the document. This guide breaks down where each unit is used, how they convert, and where people most often get caught out.

Why Indian land units are not standardised

Long before independence, land was measured and taxed by regional revenue administrations, each of which defined its own local unit for practical, on-the-ground survey work. Those units, and their exact conversion values, were never fully unified into the metric system, so they persist in land records, sale deeds and everyday conversation today, state by state.

West Bengal Bigha, Katha Maharashtra Guntha Kerala/TN Cent Nationwide Acre, Hectare
Different regions of India use different local land units

Common Indian land units

UnitCommonly used inApprox. value
BighaWB, UP, Bihar, Punjab, Haryana, Rajasthan, MP, AssamVaries by state (see table below)
KathaWest Bengal, Bihar, AssamVaries by state
DecimalBihar, West Bengal, Odisha1 Decimal ≈ 435.6 sq ft
CentKerala, Tamil Nadu, Karnataka, Andhra Pradesh1 Cent = 435.6 sq ft
GunthaMaharashtra, Karnataka1 Guntha = 1,089 sq ft
AcreNationwide (standard)43,560 sq ft
HectareNationwide (metric standard)1 Hectare = 2.471 Acres

Bigha by state: full conversion table

Bigha is the most inconsistent of all Indian land units. A property listed as "5 Bigha" means a genuinely different plot size depending on where it is, and even the smaller Katha unit it divides into is not the same everywhere:

State1 Bigha ≈Bigha divides into1 Katha (that state) ≈
West Bengal17,222 sq ft (1,600 sq m)20 Katha720 sq ft
Bihar27,220 sq ft20 Katha1,361 sq ft
Uttar Pradesh27,000 sq ft (Pucca)20 Katha1,350 sq ft
Assam14,400 sq ft5 Katha2,880 sq ft
Rajasthan27,225 sq ft (Pucca)Biswa (not Katha)
Punjab & Haryana9,070 sq ftMarla / Kanal (not Katha)
Madhya Pradesh12,000 sq ftNot commonly divided into Katha
WB Bihar UP Assam Rajasthan sq ft
Relative size of 1 Bigha across states (approximate sq ft)
Before agreeing to a price per Bigha: always confirm which state's Bigha value the seller or broker is using. A quote based on the wrong regional Bigha can misstate the actual plot size by a wide margin.

Katha and Decimal: the smaller units

For smaller residential plots, Katha and Decimal are more commonly used than Bigha:

1 Bigha (West Bengal) = 20 Katha | 1 Katha ≈ 720 sq ft (WB)
1 Decimal ≈ 435.6 sq ft | 100 Decimal = 1 Acre

Decimal is popular in Bihar, West Bengal and Odisha specifically because it maps cleanly onto Acre in round numbers, which made it convenient for revenue record-keeping.

Worked example

A plot is listed as 3 Katha in West Bengal. What is that in square feet and Decimal?

3 Katha × 720 sq ft = 2,160 sq ft

2,160 sq ft ÷ 435.6 sq ft = ≈ 4.96 Decimal

Worked example (Punjab / Haryana)

A plot in Punjab is listed as 2 Bigha. Since Punjab and Haryana use a smaller regional Bigha of about 9,070 sq ft rather than Biswa or Katha subdivisions in this comparison, the total works out simply:

2 Bigha × 9,070 sq ft = 18,140 sq ft ≈ 0.42 Acre

Guntha and Cent: regional units in the south and west

In Maharashtra and Karnataka, small plots are often quoted in Guntha, where 1 Guntha equals 1,089 square feet and 40 Guntha make up 1 Acre. In Kerala, Tamil Nadu and parts of Andhra Pradesh and Karnataka, Cent is the everyday unit, equal to 435.6 square feet, the same value as a Decimal, just under a different name used in a different region.

Acre and Hectare: the standardised units

Unlike Bigha, Katha or Guntha, Acre and Hectare do not vary by state, which is why they are used in official national land records, satellite mapping and large agricultural or industrial land deals.

1 Acre = 43,560 sq ft = 4,046.86 sq m | 1 Hectare = 2.471 Acres = 10,000 sq m

What to check on a sale deed before you rely on any unit

A broker's WhatsApp message or a verbal quote is not a legal record, and it is where most unit confusion actually starts. Before you treat any Bigha, Katha or Decimal figure as final, cross-check it against the documents that actually matter:

Where a document lists two units together, say Bigha and Decimal, use that pairing to back-calculate the exact local conversion factor being used for that specific plot and state, rather than assuming a generic value from a guide like this one.

Metric equivalents cheat sheet

Unit≈ Square Meters≈ Square Feet
1 Decimal / 1 Cent40.47 sq m435.6 sq ft
1 Guntha101.17 sq m1,089 sq ft
1 Katha (West Bengal)66.89 sq m720 sq ft
1 Acre4,046.86 sq m43,560 sq ft
1 Hectare10,000 sq m107,639 sq ft

Common mistakes when converting land units

Why use an online land area calculator

Because so many of these units depend on state-specific values, a manual conversion is one of the easier calculations to get wrong, especially when a plot listing mixes two units, say a headline size in Bigha and a rate in Decimal. An online calculator with state selection built in removes the guesswork and gives you a single trusted figure you can cross-check against the property paperwork before any money changes hands.

Key takeaways

The single most important thing to remember about Indian land units is that a name alone, Bigha, Katha or even Decimal, is not enough information to know a plot's real size. The same word carries a different value depending on the state, and sometimes the district, so the safe habit is to always ask which state's definition is being used, cross-check it against the registered sale deed or land record rather than a verbal quote, and convert everything into a standardised unit like square feet, square meters or Acre before comparing two properties or agreeing to a price. That one habit prevents almost every land-unit dispute before it starts.

Convert land units instantly

Select your state and convert between Bigha, Katha, Decimal, Cent, Guntha, Acre and Hectare in one click.

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Frequently asked questions

Is 1 Bigha the same everywhere in India?

No. Bigha is not a fixed unit and its size varies significantly by state. In West Bengal 1 Bigha is about 1,600 square meters, while in Uttar Pradesh, Bihar, Punjab, Haryana, Rajasthan and Madhya Pradesh the value is different in each state. Always confirm the local Bigha before relying on it for a transaction.

What is a Katha and how many Katha make a Bigha?

Katha is a smaller land unit common in West Bengal, Bihar, Assam and parts of Nepal. In West Bengal, 1 Bigha equals 20 Katha, while in Assam 1 Bigha equals 5 Katha, so the ratio itself also changes by state.

What is a Decimal in land measurement?

A Decimal is a widely used land unit in eastern India, especially Bihar, West Bengal and Odisha, where 1 Decimal equals approximately 435.6 square feet, and 100 Decimals make up 1 Acre.

How many square feet are in 1 Acre?

1 Acre equals 43,560 square feet, or approximately 4,046.86 square meters, and is a standardised unit that does not vary by state, unlike Bigha or Katha.

Why do land measurement units differ across Indian states?

Units like Bigha, Katha and Guntha originated from local agricultural and revenue-survey practices under different regional administrations, long before any single national standard existed, so each state's land records office kept its own conversion values, which is still reflected in property documents today.

5 Katha is equal to how many Decimal?

Using the West Bengal Katha value of approximately 720 square feet, 5 Katha equals about 3,600 square feet, which converts to roughly 8.26 Decimal. This figure changes if you are using a different state's Katha value.

How many Katha are in 1 Acre?

Using the West Bengal Katha value of approximately 720 square feet, 1 Acre (43,560 sq ft) works out to roughly 60.5 Katha. This ratio is different in states where Katha is defined differently.

How is Bigha calculated in West Bengal?

In West Bengal, 1 Bigha equals approximately 1,600 square meters or about 17,222 square feet, and is divided into 20 Katha, with each Katha equal to roughly 720 square feet.

How is Bigha converted in Bihar?

In Bihar, 1 Bigha equals approximately 27,220 square feet, which is divided into 20 Katha of about 1,361 square feet each, and works out to roughly 62.5 Decimal.

How many square feet are in 1 Decimal?

1 Decimal equals approximately 435.6 square feet, the same size as 1 Cent, which is why the two units are used interchangeably in different regions of India.

Which document should I trust for a plot's exact area?

The registered sale deed and the local revenue department's land record (such as Khatian, Jamabandi or RTC depending on the state) carry the legally binding area figure, and should be checked over any verbal quote or broker estimate before relying on a converted unit.

How many square meters are in 1 Katha?

Using the West Bengal value, 1 Katha is approximately 66.89 square meters, though this figure changes in states like Bihar or Assam where Katha is defined differently.

EH
Written by Ekramul Haque
Founder of EkZapp · builds free utility tools for construction, PDF and everyday calculations
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