The formula
Every conversion goes through square feet:
Result = amount × (sq ft in the first unit) ÷ (sq ft in the second unit)
For decimal to katha: decimal × 435.6 ÷ 720.
Examples
How many katha is 10 decimal? 10 × 435.6 = 4,356 sq ft. Then 4,356 ÷ 720 = 6.05 katha. In bigha that is 4,356 ÷ 14,400 = 0.3025 bigha.
How many decimal is 3 katha? 3 × 720 = 2,160 sq ft. Then 2,160 ÷ 435.6 ≈ 4.96 decimal, or almost 5 decimal.
Conversion table
| Unit | Square feet | Decimal |
|---|---|---|
| 1 ojutangsho | 4.356 | 0.01 |
| 1 decimal (shotok) | 435.6 | 1 |
| 1 katha | 720 | ≈ 1.65 |
| 1 bigha (20 katha) | 14,400 | ≈ 33.06 |
| 1 acre | 43,560 | 100 |
| 1 hectare | ≈ 107,639 | ≈ 247.11 |
| 1 square metre | ≈ 10.76 | ≈ 0.0247 |
| 1 square yard | 9 | ≈ 0.0207 |
| 1 square haat (cubit) | 2.25 | ≈ 0.0052 |
Popular conversions
Conversion rules: Decimal to katha · Katha to decimal · Decimal to sq ft · Bigha to decimal · Acre to decimal · Katha to sq ft · Bigha to katha
Decimal (shotok): 1 decimal · 5 decimal · 10 decimal · 20 decimal · 33 decimal · 50 decimal · 100 decimal
Katha, bigha and more: 1 katha · 3 katha · 5 katha · 1 bigha · 1 acre · 1 gonda · 1000 sq ft
What to know in Bangladesh
- Shotok, shotangsho and decimal are the same unit. Official papers usually say “shotangsho”; people say “shotok”.
- The standard katha and bigha are used in Dhaka and most areas: 1 katha = 720 sq ft, and 1 bigha = 20 katha. Some places still use older local measures.
- Gonda and kani are regional. This calculator uses the common values: 1 gonda ≈ 2 decimal and 1 kani ≈ 40 decimal. In parts of Sylhet a kani is larger.
- Before buying or selling, match the deed, khatian and map. If needed, have a surveyor (amin) measure the land.
More: where these units come from
Two systems run side by side in Bangladesh. One is the British-era acre and its hundredth, the decimal (shotok). The other is the local units: katha, bigha, gonda and kani.
Acre and decimal: 1 acre = 43,560 sq ft. A hundredth of an acre is 1 decimal = 435.6 sq ft, and a hundredth of a decimal is 1 ojutangsho = 4.356 sq ft. Land office records, deeds and khatians usually use these units.
Katha and bigha: katha is the everyday unit for city plots. The standard katha is 720 sq ft (for example 24 ft × 30 ft), and 20 katha make a bigha. People often call a bigha “33 decimal”; the exact value is 33.06.
Measuring by haat: in villages land is still often measured in haat (cubits). 1 haat = 18 inches = 1.5 ft, so 1 square haat = 2.25 sq ft. Multiply length by width in haat, then choose “square haat” here to convert.
Irregular plots: if the four sides differ, you first need the area, not just a unit conversion. A separate land area calculator is coming.