Land Measurement Calculator in Bangladesh — Shotok, Katha, Bigha, Acre & Heron's Precision Formula
TulBD Land Measurement Calculator in Bangladesh is an advanced, high-precision digital surveying suite engineered to compute accurate land areas and convert traditional land measurement units. In Bangladesh, land transactions, inheritance partition, and boundary disputes often suffer from inaccuracies caused by traditional surveyors applying simplistic arithmetic averages on non-rectangular quadrilateral plots. Our intelligent calculator eliminates errors by integrating both standard surveyor rules and mathematically rigorous Heron's Formula, delivering legally bulletproof calculations in Shotok (Decimal), Katha, Bigha, Acre, Square Feet, and Square Meters.
Official Bangladesh Land Measurement Conversion Standards
Standard land area units recognized by the Ministry of Land and the Directorate of Land Records and Surveys (DLRS) are detailed below:
| Unit Name | Square Feet (Sq. Ft.) | Shotok / Decimal Value | Equivalent Conversions |
|---|---|---|---|
| 1 Shotok / Decimal | 435.60 Sq. Ft. | 1.000 Shotok | 1,000 Sq. Links / 48.4 Sq. Yards / 40.468 Sq. Meters |
| 1 Katha | 720.00 Sq. Ft. | 1.6528 Shotok | 16 Chhatak / 80 Sq. Yards / 66.89 Sq. Meters |
| 1 Bigha | 14,400.00 Sq. Ft. | 33.0578 Shotok | 20 Katha / 1,600 Sq. Yards / 1,337.8 Sq. Meters |
| 1 Acre | 43,560.00 Sq. Ft. | 100.00 Shotok | 3 Bigha 8 Chhatak (3.025 Bigha) / 4,046.86 Sq. Meters |
| 1 Hectare | 107,639.10 Sq. Ft. | 247.105 Shotok | 2.471 Acres / 10,000 Sq. Meters / 7.47 Bigha |
| 1 Gunter Link | 0.4356 Sq. Ft. per link² | 1,000 Sq. Links = 1 Shotok | 1 Chain = 66 Ft = 100 Links (1 Link = 7.92 Inches) |
Why the Traditional Surveyor Average Method Causes Severe Errors
Most field surveyors in rural Bangladesh calculate 4-sided plots by averaging opposing sides:
Area (Average Method) = [ (North + South) ÷ 2 ] × [ (East + West) ÷ 2 ]
The Mathematical Flaw: This formula is mathematically valid only if all four interior corners form exact 90-degree right angles (a true rectangle). In realistic land parcels, angles deviate from 90 degrees. Using the average method invariably overestimates the true land area, sometimes by several decimals, leading to buyer disputes and boundary conflicts.
The Heron's Formula Solution: By measuring an interior diagonal line between two opposite corners, the quadrilateral is divided into two distinct scalene triangles. Heron's formula calculates the area of each triangle with 100% geometric accuracy:
Semi-perimeter, s = (a + b + c) ÷ 2 Triangle Area = √[ s × (s - a) × (s - b) × (s - c) ] Total Area = Triangle 1 Area + Triangle 2 Area
Features of TulBD Land Measurement Suite
- Multi-Geometry Support: Calculate irregular 4-sided plots, triangles, trapezoids, circles, and composite multi-segment parcels.
- Multi-Unit Flexibility: Input in Feet & Inches, Gunter's Links (Cadastral survey chains), Meters, Yards, or traditional Haats.
- Real-Time SVG Visualizer: Dynamic scaling canvas displaying parcel shapes, directional bearings (North, South, East, West), diagonals, and dimension markers.
- Inheritance & Partition Divider: Allocate land shares among legal heirs by percentage or fractions with immediate Decimal and Square Foot results.
- Mouza Map Scale Converter: Converts Gunia markings and chain links across 16", 32", and 64" = 1-mile map sheets.
- Printable Official Survey Report: Generates formatted legal documentation with client names, Mouza, Khatian, Daag numbers, and surveyor signature blocks.
Frequently Asked Questions (FAQ)
Q1: How many square feet are in 1 Shotok (Decimal) and 1 Katha?
Answer: In Bangladesh, 1 Shotok (Decimal) equals exactly 435.60 square feet. 1 Katha equals 720.00 square feet (or approximately 1.6528 Shotok).
Q2: What is the most accurate way to measure irregular 4-sided land?
Answer: The only 100% mathematically accurate method for irregular 4-sided land is measuring an interior diagonal (Korn) to divide the quadrilateral into two triangles, and then computing both areas using Heron's Formula. Relying on average lengths produces significant errors on non-rectangular plots.
Q3: How many Shotok are in 1 Bigha and 1 Acre?
Answer: Standard government records define 1 Bigha as 20 Katha or 33.0578 Shotok (commonly referenced as 33 decimals or 14,400 sq. ft.). 1 Acre is exactly 100 Shotok (43,560 sq. ft., or approximately 3.025 Bigha).
Q4: How do Gunter's Chains and Links convert to feet?
Answer: A standard Gunter's Chain is 66 feet long and composed of 100 links. Therefore, each link is 7.92 inches or 0.66 feet. In area calculations, exactly 1,000 square links equal 1 Shotok.
Q5: Does Kani have different values across different districts?
Answer: Yes. The official government standard Kani is 160 Shotok (Shahi Kani). However, in Chattogram and Noakhali districts, a Kani is traditionally counted as 40 Shotok (or 120 Shotok in certain rural pockets). Our calculator includes an regional selector to match your specific district standard.