Convert bigha to katha — state by state
To convert bigha to katha, multiply by the size of one bigha in your state and divide by the size of one katha. East Indian land records count bigha, katha and smaller units together, and the number of katha in a bigha is not the same in every state. This converter keeps the local definitions apart: pick the state or region first, then type in either box.
One bigha is anything from 5 to 20 katha depending on where the land is, so a single “standard” figure from a search result can be badly wrong. Each value below says where it comes from — a state revenue rule or land-records publication where one exists, otherwise it is marked as a commonly used value that you should confirm with the tehsil, the sub-registrar or a licensed surveyor.
How to use the Bigha to Katha
- Choose the state or region at the top — the default is Bihar (Patna region).
- Type the area into the first box; the katha appear in the second box, in the result panel and in the formula line.
- Type into the second box instead to convert katha back to bigha, or press the swap button.
- Read the table to see the same area in every unit used in that state, with the basis of each value. Tap a row to make it the target unit.
- If your record uses a different size, pick Custom and enter the bigha, katha or marla size from your sale deed.
Bigha to Katha features
State selector first
Every bigha value is tied to a state or district group, so Bihar and Assam never get mixed up.
Cited values
Government sources are linked under the selector and in the table; anything else is labelled “confirm locally”.
Both directions
Type bigha or katha — the other box follows, with the working shown.
Custom sizes
Enter your own bigha, katha or marla size when your village uses a local measure.
How big is one bigha in each state?
Values are stored in square feet. “Definition” means an exact unit such as the acre; a linked source is a state government publication (checked October 2026).
| State or region | 1 bigha | In katha | Basis |
|---|---|---|---|
| West Bengal | 14,400 sq ft | 20 katha | NIC for the Department of Land Resources, 2016 |
| Assam | 14,400 sq ft | 5 katha | Directorate of Economics & Statistics, Assam (2019) |
| Bihar (Patna region) | 27,225 sq ft | 20 katha | Revenue & Land Reforms Department, Bihar (approved Oct 2025) |
| Bangladesh | 14,400 sq ft | 20 katha | Common — confirm locally |
Bigha to katha formula
Katha = bigha ×(sq ft in one bigha) ÷ (sq ft in one katha). Worked examples:
- 1 bigha in Bihar: 1 × 27,225 ÷ 1,361.25 = 20 katha
- 5 bigha in Bihar: 5 × 27,225 ÷ 1,361.25 = 100 katha
- 2 bigha in Assam: 2 × 14,400 ÷ 2,880 = 10 katha
Bigha to katha table for Bihar
Using 1 bigha = 20 katha. Pick another state above for its own figures.
| Bigha | Katha |
|---|---|
| 0.25 bigha | 5 katha |
| 0.5 bigha | 10 katha |
| 1 bigha | 20 katha |
| 2 bigha | 40 katha |
| 3 bigha | 60 katha |
| 4 bigha | 80 katha |
| 5 bigha | 100 katha |
| 10 bigha | 200 katha |
| 20 bigha | 400 katha |
| 50 bigha | 1,000 katha |
| 100 bigha | 2,000 katha |
Bigha to Katha FAQ
How many katha are in 1 bigha?
It depends on the state: West Bengal 20, Assam 5, Bihar 20, Bangladesh 20. Pick your state in the converter to see the figure and its source.
Why is a bigha 5 katha in Assam but 20 in Bihar?
They are different systems. In Assam 1 bigha = 5 katha = 100 lessa (14,400 sq ft), so a katha is 2,880 sq ft; in Bihar and West Bengal a bigha is 20 katha and the katha is much smaller.
Is the bigha the same everywhere in India?
No. The bigha grew out of local revenue systems, so its size changes between states and sometimes between districts and villages. Rajasthan’s 1957 land-record rules, for example, list five different chain lengths for the bigha.
Which bigha value should I use for a sale deed?
Use the figure in your land record (khatauni, jamabandi, RTC or 7/12) or ask the sub-registrar. Registration and stamp duty are worked out on the official area, usually in hectares, acres or square metres.
How do I convert katha back to bigha?
Divide by the same factor — for Bihar, divide by 20. Or type the value into the second box above.