A land listing says 20 guntha, a relative talks about “a few bigha” back in the village, and a Kerala plot is sold by the cent. All three describe area, but none of them is a size you can picture. The good news: one short formula converts any of them into square feet or acres, as long as you know the size of a single unit.
Why these units are so confusing
Bigha, guntha and cent are traditional land units still used across the Indian subcontinent. Official land records now use hectares, acres, square meters or square yards, but agricultural and residential deals are still often discussed informally in the old units.
The catch is that the three units don’t behave the same way. The guntha and the cent are tied to the acre by a fixed ratio. The bigha is not: its size changes from one region to the next, from around 6,806 square feet to 27,225 square feet on average.
The size of one unit
Everything starts with the size of a single unit. Here are the reference values:
- Guntha (Maharashtra and other parts of India): 33 ft × 33 ft = 1,089 sq ft, or about 101.17 m². 40 guntha = 1 acre.
- Cent (Kerala, Tamil Nadu, Karnataka, Andhra Pradesh, Telangana): 1/100 of an acre = 435.6 sq ft, or about 40.47 m².
- Bigha, West Bengal, Assam and Bangladesh: 14,400 sq ft (1,600 square yards), so 1 acre = 3.025 bigha.
- Bigha, Bihar (Patna): 27,225 sq ft, split into 20 katha of 1,361.25 sq ft each.
- Bigha, Punjab and Haryana: 21,780 sq ft, so 2 bigha = 1 acre.
- Bigha, Himachal Pradesh: 8,712 sq ft, so 5 bigha = 1 acre.
The anchor number to remember is the acre: 1 acre = 43,560 square feet exactly. Every unit above is just a fraction of it.
The formula, in plain words
To get square feet, multiply the number of units by the size of one unit. To get acres, divide that result by 43,560:
Square feet = number of units × size of one unit (in sq ft), then acres = square feet ÷ 43,560
To switch directly from one traditional unit to another, go through square feet: multiply by the size of the first unit, then divide by the size of the second.
A real example: one 20 guntha plot, six different numbers
Take a 20 guntha plot in Maharashtra.
- In square feet: 20 × 1,089 = 21,780 sq ft
- In square meters: 20 × 101.1714 = about 2,023 m²
- In acres: 21,780 ÷ 43,560 = 0.5 acre (or simply 20 ÷ 40)
- In cents: 21,780 ÷ 435.6 = 50 cents
- In Punjab or Haryana bigha: 21,780 ÷ 21,780 = exactly 1 bigha
- In West Bengal bigha: 21,780 ÷ 14,400 = about 1.51 bigha
- In Bihar bigha: 21,780 ÷ 27,225 = 0.8 bigha
- In Himachal Pradesh bigha: 21,780 ÷ 8,712 = 2.5 bigha
Same land, yet the bigha figure ranges from 0.8 to 2.5 depending on which state’s definition you use.
A quick reverse check works too. A 10 cent plot in Kerala is 10 × 435.6 = 4,356 sq ft, which is 0.1 acre, or 4,356 ÷ 1,089 = 4 guntha. A handy shortcut falls out of this: 1 guntha = 2.5 cents.
Common mistakes to avoid
Using one bigha value for all of India
This is the big one. Five bigha in West Bengal is 5 × 14,400 = 72,000 sq ft (about 6,690 m²). Five bigha in Bihar is 5 × 27,225 = 136,125 sq ft, almost double. Always confirm which region’s bigha the seller or relative means before converting anything.
Mixing up subdivisions
Each unit has smaller parts. A guntha is divided into 16 anna (about 6.32 m² each), and a bigha is commonly divided into 20 katha, although Assam uses 5 katha per bigha. An anna or a katha is not an independent unit at the same scale, so convert it back to its parent unit first.
Thinking the cent is something else
In land deals, a cent has nothing to do with money: it is simply 1/100 of an acre. In West Bengal and Bangladesh, that exact same 1/100 acre is called a “decimal”. Different name, identical size.
Forgetting what the official papers say
Because land registries now record areas in hectares, acres, square meters or square yards, the traditional figure you hear in conversation should always be checked against the registered area before any payment.
Convert your own plot
If your land record lists the area in hectares, ares or square meters, the 7/12 calculator converts it straight into acres, guntha and square feet. For bigha, keep the regional list above at hand: once you know the size of one unit, the rest is a single multiplication.
