Katha to Decimal Converter – Complete Bihar Land Measurement Guide

Quick Answer: In Bihar, 1 Katha = 3.415 Decimal. One Katha divides into 20 Dhur, and each Dhur contains 20 Dhurki — making 400 Dhurki per Katha. Use the free calculator above to convert instantly.

Whether you are buying agricultural land in Patna, registering a plot in Darbhanga, or verifying your Jamabandi records in Muzaffarpur, understanding how to convert Katha to Decimal is essential. Bihar’s traditional land measurement system uses Katha, Dhur, and Dhurki alongside modern units like Decimal and Acre, and confusion between them can lead to costly errors in property documents.

This guide explains every conversion you need, how the Bihar system works, how it compares with other states, and how to avoid the most common mistakes in land transactions.

What Is a Katha? (Bihar Definition)

Katha (also spelled Kattha or Cottah) is a traditional land measurement unit used across Bihar, West Bengal, Jharkhand, Assam, and parts of Nepal and Bangladesh. The origin of the Katha measurement unit dates back to the Pala Empire, and while it became officially obsolete after metrication in the mid-20th century, it remains in active use in Bihar’s land records and property transactions.

One of the most important things to understand is that the value of one Katha is not universally standardised and can differ significantly from one location to another. In Bihar specifically, 1 Katha is equal to 20 Dhur, 1 Dhur is equal to 20 Dhurki, and 1 Katha equals 1,361 square feet.

⚠️ Important: The Katha used in Bihar is different from the Katha used in West Bengal (720 sq ft) and Assam (2,880 sq ft). Always confirm which regional standard applies to your land documents.

Bihar’s Katha hierarchy at a glance

Unit	Equals	Square Feet
1 Dhurki	—	3.403 sq ft
1 Dhur	20 Dhurki	68.06 sq ft
1 Katha	20 Dhur / 400 Dhurki	1,361.25 sq ft
1 Bigha	20 Katha	27,220 sq ft

Katha to Decimal Conversion in Bihar

Decimal (also called Dismil or Shotangsha) is a widely used unit in Bihar and eastern India. One Decimal is 1/100th of an acre and is equivalent to 435.6 square feet. It was introduced as part of land reform programs to simplify official records.

Using the standard Bihar measurement where 1 Katha = 1,361.25 sq ft:

1 Katha ÷ 435.6 sq ft per Decimal = 3.125 Decimal (Patna/Arrah standard)
The commonly used practical rate across most of Bihar is 3.415 Decimal per Katha.

Bihar’s land measurement system relies on Bigha, Katha, Decimal, and Dhur — with Decimal being a modern unit used alongside traditional ones, primarily in official documents.

Complete Katha to Decimal conversion table (Bihar)

Katha	Decimal	Dhur	Dhurki
0.5 Katha	1.7075 Decimal	10 Dhur	200 Dhurki
1 Katha	3.415 Decimal	20 Dhur	400 Dhurki
2 Katha	6.83 Decimal	40 Dhur	800 Dhurki
3 Katha	10.245 Decimal	60 Dhur	1,200 Dhurki
5 Katha	17.075 Decimal	100 Dhur	2,000 Dhurki
10 Katha	34.15 Decimal	200 Dhur	4,000 Dhurki
20 Katha	68.3 Decimal	400 Dhur	8,000 Dhurki
1 Bigha (20 Katha)	68.3 Decimal	400 Dhur	8,000 Dhurki

Dhur to Decimal conversion table

Dhur	Decimal	Square Feet
1 Dhur	0.17075 Decimal	68.06 sq ft
5 Dhur	0.854 Decimal	340.3 sq ft
10 Dhur	1.7075 Decimal	680.6 sq ft
20 Dhur	3.415 Decimal	1,361.25 sq ft

How to Convert Katha to Decimal — Step by Step

Formula: Katha to Decimal

Decimal = Katha × 3.415

Example 1: You want to convert 4 Katha to Decimal.

• 4 × 3.415 = 13.66 Decimal

Example 2: Convert 2 Katha 10 Dhur to Decimal.

• Convert total to Katha: 2 + (10 ÷ 20) = 2.5 Katha
• 2.5 × 3.415 = 8.5375 Decimal

Formula: Decimal to Katha

Katha = Decimal ÷ 3.415

Example: You have 20 Decimal. How many Katha is that?

• 20 ÷ 3.415 = 5.86 Katha (approximately 5 Katha 17 Dhur 2 Dhurki)

💡 Tip: Use the free calculator at the top of this page to handle any combination of Katha, Dhur, and Dhurki automatically — no manual arithmetic needed.

Bihar Land Measurement — Unit Comparison by State

Katha to Decimal conversion varies significantly across Indian states because Katha is a traditional, non-standard land measurement unit. In Bihar, 1 Katha is commonly around 3.125 Decimal, while in West Bengal it may vary between 1.5 to 2 Decimal depending on the district. In Assam, 1 Katha is often considered 2.66 Decimal.

State	1 Katha in Sq Ft	1 Katha in Decimal	Notes
Bihar	1,361.25 sq ft	~3.125–3.415 Decimal	Varies by district; 3.415 most common
West Bengal	720 sq ft	~1.652 Decimal	Standardised for urban/rural
Jharkhand	270–720 sq ft	~0.62–1.65 Decimal	Varies widely by district
Assam	2,880 sq ft	~6.61 Decimal	Much larger unit than Bihar
Bangladesh	720 sq ft	~1.652 Decimal	Officially standardised

This is why using a calculator without selecting the correct region can give completely wrong results. Our calculator lets you select Bihar or enter a custom rate for your specific district.

Bihar Land Laws You Should Know

Land measurement in Bihar is governed by several important laws:

1. Bihar Land Reforms Act, 1950 — Played a pivotal role in redistributing land from zamindars to tenants, leading to a need for precise measurements.
2. Bihar Land Mutation Act, 2011 — Streamlined the process by ensuring that land records are updated promptly.
3. Bihar Special Survey and Settlement Act, 2011 — Introduced modern technology for accurate land surveys, reducing disputes over land measurement.

While modern urban deeds (Sale Deeds) often use metric units like Hectares or imperial units like Acres, the ancestral land records — specifically the Record of Rights (RoR) — often retain traditional measurements. Accurate conversion is mandatory for calculating Stamp Duty, Circle Rates, and resolving partition disputes in local courts.

How to Read Your Bihar Land Record (Khatauni/Jamabandi)

Bihar’s official land records are maintained on the Bihar government’s Bhumi portal. When you access your Khatauni (Record of Rights), land area may be recorded in any of these formats:

• Decimal / Dismil — most common in official documents
• Acre — used for larger parcels
• Katha / Dhur — appears in older records and rural transactions
• Square metres / Hectares — modern metric records

To verify your land area accurately, start by checking the land’s historical records, as they often include measurements in traditional units such as Bigha, Katha, or Dhur. Then use established conversion tables to translate traditional units into modern equivalents like square meters, acres, or hectares.

Before buying land in Bihar, always verify measurements through:
Sale deed · Mutation records (Dakhil Kharij) · Revenue records (Khatauni) · Survey documents (Khesra) · Registration documents

Complete Bihar Land Unit Reference Chart

Conversion	Value
1 Dhurki	3.403 sq ft / 0.3161 sq m
1 Dhur	20 Dhurki / 68.06 sq ft / 6.322 sq m
1 Katha	20 Dhur / 400 Dhurki / 1,361.25 sq ft / 126.4 sq m
1 Katha	3.415 Decimal
1 Bigha	20 Katha / 400 Dhur / 27,220 sq ft
1 Acre	32 Katha / 1.6 Bigha / 100 Decimal / 43,560 sq ft
1 Decimal	435.6 sq ft / 40.47 sq m
1 Hectare	2.47 Acres / ~79 Katha

Frequently Asked Questions

What is 1 Katha in Decimal in Bihar?

In Bihar, 1 Katha equals 3.415 Decimal. This is the standard conversion used across most of the state, including Patna, Darbhanga, Muzaffarpur, Gaya, and Bhagalpur. Some districts around Patna/Arrah use 3.125 Decimal — always check your local revenue office.

How many Dhur make 1 Katha in Bihar?

1 Katha is divided into 20 Dhur in Bihar. One Dhur is further subdivided into 20 Dhurki.

How many Dhurki are in 1 Katha?

1 Katha = 20 Dhur × 20 Dhurki = 400 Dhurki.

How do I convert Decimal to Katha manually?

Divide the Decimal value by 3.415. For example: 25 Decimal ÷ 3.415 = 7.32 Katha (approximately 7 Katha 6 Dhur 8 Dhurki). Use the calculator above for exact Katha + Dhur + Dhurki breakdown.

Is 1 Katha the same across all Bihar districts?

Bihar exhibits significant variations at the Tehsil level, often due to historical administrative divisions where local rulers standardised the measuring chain (Gatha) length differently. For example, a Bigha in Magadh/Patna may differ significantly from one in neighbouring districts. Always consult your Khatauni or local revenue office for the precise rate.

What is 1 Decimal in square feet?

1 Decimal = 435.6 square feet. It represents 1/100th of an acre.

How many Katha make 1 Bigha in Bihar?

1 Bigha = 20 Katha in Bihar. So 1 Bigha = 68.3 Decimal or approximately 27,220 square feet.

How many Katha in 1 Acre in Bihar?

1 Acre = 32 Katha in Bihar, calculated as 1 Acre = 1.6 Bigha, and 1 Bigha = 20 Katha, so 1.6 × 20 = 32 Katha.

Why does Katha differ between states?

Land measurement systems developed independently across regions during historical land revenue administration. As a result, there is no single national standard for Katha. Each state or even district defines its own conversion, so always refer to local revenue records or official land departments for accurate and legally valid state-wise conversions.

Can I use this calculator for land registration in Bihar?

This calculator is designed for quick reference and estimation. For official property registration, stamp duty calculation, or legal land documentation, always verify the final figures with the Bihar Revenue Department or a registered land surveyor. Conversion rates can vary by district and document type.

Conclusion

Bihar’s land measurement system is rich in history but can be confusing — especially when traditional units like Katha, Dhur, and Dhurki appear alongside modern Decimal and Acre measurements. The key conversion to remember is 1 Katha = 3.415 Decimal, with 1 Katha breaking down into 20 Dhur and 400 Dhurki.

Use our free Katha to Decimal Converter above to instantly convert any combination in both directions — whether you are checking a sale deed, calculating land value, or verifying your Record of Rights online.

For any official transaction — registration, mutation, or loan against property — always cross-check your calculations with your local tehsil office or Bhumi Bihar portal records. Accurate land measurement protects your investment and prevents legal disputes.