The katha (also spelt kattha) is a common land unit in eastern India — Bihar, Jharkhand, West Bengal and parts of Assam. Like the bigha it's part of, its size varies by state, so "1 katha in square feet" has different answers in different places.
Katha varies by state and sometimes district. The figures below are commonly-cited values — always confirm against local land records before acting.
Common katha values
- Bihar / Jharkhand: 1 katha ≈ 1,361 sq ft (20 katha = 1 bigha).
- West Bengal: 1 katha ≈ 720 sq ft (a smaller katha).
- Assam: commonly around 2,880 sq ft in some areas.
Because the katha is a subdivision of the local bigha, wherever the bigha differs, the katha differs too.
Katha, bigha and biswa
In the eastern system, a bigha is divided into kathas, and a katha can be further divided (into dhur, chatak, etc., depending on the region). So reading a plot in "3 katha" means very different areas in Patna vs Kolkata.
How to convert your katha
Use the free converter and pick your state for the correct local value: katha to square feet, katha to bigha, or the full Land Area Converter.
For more on the units around it, see bigha state-by-state and land units in India explained.
Always confirm the exact katha value for your district before you buy, sell or register land.