If you are looking to buy a residential plot or agricultural land in Bihar, the word you will hear most often is "Kattha".
Unlike in metro cities where "Square Feet" is the standard, land deals in Patna, Darbhanga, and Gaya rely entirely on the traditional Kattha system. But here is the problem: a Kattha in one district might be a completely different size than a Kattha in the neighboring district.
If you don't know the math, you risk paying the price of a large plot for a much smaller piece of land.
This guide clarifies the confusion. We will break down the standard conversion of Kattha to Square Feet in Bihar, explain why the size changes, and give you a simple table to calculate the value yourself.
Quick Takeaways
- The Standard Value: In most of Bihar (Patna standard), 1 Kattha ≈ 1,361 Square Feet.
- The Variation: The size depends on the "Laggi" (measuring pole) used in the village.
- Relation to Bigha: 20 Katthas make 1 Bigha.
- Best for: Measuring standard residential plots (e.g., building a house).
What is a Kattha?
The Kattha (sometimes spelled Katha or Cottah) is a unit of area used principally in Eastern India (Bihar, Jharkhand, West Bengal) and Nepal.
It sits right in the middle of the land measurement hierarchy. It is bigger than a Dhur but smaller than a Bigha. Because it represents a manageable size for a family home (usually 1,000+ sq ft), it is the most popular unit for selling residential plots.
Kattha to Square Feet: The Formula (Bihar Standard)
While local variations exist, for most legal registrations and urban property deals in Bihar, the standard conversion is based on the 5.5 Hand Laggi.
The Calculation Steps
If you have a land area in Kattha and want to compare it with apartment sizes in square feet:
Formula:Area in Sq Ft = Area in Kattha × 1,361
Example:
You are looking at a 2 Kattha plot in Patna.
2 × 1,361 =
2,722 Sq Ft.
To put that in perspective, 2,722 sq ft is massive—roughly the size of two large 3-BHK luxury apartments combined.
Quick Conversion Table (Kattha to Sq Ft)
Here is a quick reference table for common plot sizes you will see in advertisements.
| Area in Kattha | Area in Sq Ft (Approx) | Common Usage |
|---|---|---|
| 0.5 Kattha | 680 sq ft | Small budget house / Shop |
| 1 Kattha | 1,361 sq ft | Standard family home plot |
| 1.5 Kattha | 2,041 sq ft | Spacious bungalow plot |
| 2 Kattha | 2,722 sq ft | Large villa or duplex |
| 5 Kattha | 6,806 sq ft | Commercial complex / Apartment building |
| 10 Kattha | 13,612 sq ft | Half Bigha (Small farm) |
| 20 Kattha | 27,225 sq ft | 1 Full Bigha |
Visualizing scale: A standard home fits comfortably in 1 Kattha
The "Laggi" Confusion: Why Size Matters
This is the most critical part of buying land in Bihar. The "Standard" we mentioned above (1,361 sq ft) is based on a 5.5 Haath ki Laggi (5.5 cubits measuring rod).
However, different districts use different Laggi sizes:
4 Haath Laggi
1 Kattha ≈ 720 Sq Ft
5.5 Haath Laggi
1 Kattha ≈ 1,361 Sq Ft (Standard)
6.5 Haath Laggi
1 Kattha ≈ 1,901 Sq Ft
Warning: If a broker offers you land at a "very cheap rate per Kattha," ask immediately about the Laggi size. They might be selling you a 720 sq ft Kattha while you are assuming it is 1,361 sq ft.
Kattha vs. Decimal
Because Kattha varies, many modern registries now prefer using "Decimal" because it is a fixed unit (1/100th of an Acre).
- 1 Kattha (Standard) ≈ 3.125 Decimals
- 1 Decimal = 435.6 Sq Ft
If you want to be 100% safe, ask the seller to mention the area in Decimals or Square Feet on the agreement.
How to Convert Kattha to Other Units
Here is how Kattha stacks up against other common units in the region.
| Unit | Value in Kattha (Standard) |
|---|---|
| 1 Bigha | 20 Kattha |
| 1 Acre | ~32 Kattha |
| 1 Hectare | ~79 Kattha |
| 1 Dhur | 1/20th of a Kattha |
Land measurement hierarchy: 20 Dhur = 1 Kattha, 20 Kattha = 1 Bigha
Frequently Asked Questions
1. How many square feet is 1 Kattha in Patna?
In Patna and most central Bihar districts, 1 Kattha is generally calculated as 1,361.25 square feet.
2. How many Decimals are in 1 Kattha?
In the standard system (5.5 hand Laggi), 1 Kattha equals 3.125 Decimals.
3. Is Kattha size the same in Bihar and Jharkhand?
Mostly, yes. Both states largely follow the 1 Kattha = 1,361 sq ft standard, but rural variations exist in both. Always check the local circle rate norms.
4. How many Katthas make 1 Acre?
Approximately 32 Katthas make 1 Acre (assuming the standard 1,361
sq ft size).
Calculation: 43,560 (Acre) ÷ 1,361 (Kattha) = 32.005.
5. Can I get a home loan based on Kattha measurement?
Banks will convert your Kattha measurement into Square Feet to value the property. If your deed says "1 Kattha" but the actual land is only 720 sq ft (due to small Laggi), the bank will value it at 720 sq ft, potentially lowering your loan amount.
6. What is "Dhur" in relation to Kattha?
Dhur is a sub-unit. There are 20 Dhurs in 1 Kattha. If you buy half a Kattha, it is often written as "10 Dhur".
7. How many square yards (Gaj) is 1 Kattha?
Since 1 Kattha ≈ 1,361 sq ft and 1 Sq Yard = 9 sq ft:
1,361 ÷ 9
= 151.2 Square Yards (approx).
Conclusion
Buying land in Bihar is a great investment, but it requires vigilance regarding measurements. The "Kattha" is a flexible unit, and its value changes depending on where you stand.
To protect your investment:
- Assume 1 Kattha = 1,361 sq ft for general searches.
- Verify the specific "Laggi" measuring pole used in that village (4, 5.5, or 6.5 hands).
- Finalize the deal based on the total Square Feet or Decimal area written in the sale deed.
Don't rely on verbal promises. Measure the land, do the math, and sign with confidence!