Bigha, kattha and dhur
SajiloTools uses 1 bigha = 20 kattha = 400 dhur = 72,900 square feet, and 1 dhur = 182.25 square feet. Some offices still use a smaller bigha.
The Terai chain in the converter
1 dhur = 182.25 square feet.
20 dhur = 1 kattha = 3,645 square feet.
20 kattha = 1 bigha = 400 dhur = 72,900 square feet.
Hill units stay separate: 1 ropani is 5,476 square feet, not one bigha. A Terai dhur (182.25 square feet) is not a hill daam (about 21.39 square feet).
72,900 is not the only bigha people quote
Some offices and older local practice use a smaller bigha, including a 27,000 square foot convention. SajiloTools follows the 72,900 square foot chain, not 27,000.
Check the lalpurja or the office that will accept the number before you rely on one conversion.