Katha to Square Feet: 720, 1,361, 2,880 or 3,645, by Region
Katha (kattha, cottah) to square feet, square metres and gaj by region: Kolkata 720, Guwahati 2,880, Patna about 1,361, Nepal 3,645. Each figure graded.
Katha to Square Feet — 720, 1,361, 2,880 or 3,645, by region
A katha is one rung under a bigha, and the bigha it sits under changes size by state. Kolkata means 720 ft²; Guwahati means 2,880; Patna means about 1,361; the Nepal Terai means 3,645. Pick the region first, and this page tells you how well each figure is sourced.
Search "katha to square feet" and the first answer you get is 720. That is the right answer for a Kolkata listing and the wrong answer, by a factor of four, for a plot in Guwahati. The katha (also spelt kattha and cottah) is defined as a share of the local bigha, and the local bigha is not one size, so the katha inherits every disagreement the bigha has and adds one of its own: in Assam the share is a fifth, everywhere else it is a twentieth.
The 720 ft² figure is the Bengal one: twenty katha to a 14,400 ft² bigha, which makes a katha exactly 80 square yards, or gaj. It is what Kolkata, Howrah and the south Bengal districts mean, and it is the same figure Bangladesh publishes. Assam's Brahmaputra Valley puts five katha to the same 14,400 ft² bigha, so a katha there is 2,880 ft². Bihar's own glossary gives the Patna katha only as "approx. 1361 sq ft" and says it varies by region. Nepal's Terai runs 20 katha to a 72,900 ft² bigha, 3,645 each.
So this page asks which katha before it converts, grades every figure by the document behind it, and declines to give a number where no document does. The bigha itself, with its state-by-state schedule, is on this site's bigha page; this page carries only the ladders that have a katha in them.
| Katha | — |
|---|---|
| Square feet | — |
| Square metres | — |
| Gaj (square yards) | — |
| Acres · decimal | — |
| Bigha on this ladder | — |
| One katha here | — |
| 2 · 3 · 5 · 10 katha | — |
| How good is this figure | — |
| If the other katha was meant | — |
The katha is not a unit. It is a fraction, and the thing it is a fraction of moves. Every ladder here defines the katha by division: a twentieth of the bigha in Bengal, Bihar, Bangladesh and Nepal, a fifth of it in the Brahmaputra Valley. Nobody fixes the katha and derives the bigha from it. So the question “how many square feet in a katha” is really two questions, how big is the bigha here and how many katha does it hold, and a converter that prints one number has answered both without asking either. The four bigha sizes that carry a katha are 14,400 ft² (Bengal, Assam, Bangladesh), about 27,225 (Patna), 72,900 (Nepal Terai) and the 12,000 that Madhya Pradesh brokers use, and the two ladders give a range of 600 to 3,645 ft² for one word. That is a 6× spread, and the 4× step between Guwahati and Silchar sits inside one state.
Kolkata's 720 ft² is a survey figure, and no statute repeats it. The number comes from the Bengal measure as a 1900 survey manual sets it out: 14,400 ft² to the bigha, 20 katha to the bigha, 16 chatak to the katha, so a katha is 720 ft², exactly 80 gaj, and a chatak is 45. The West Bengal Land Reforms Act, 1955 uses the words bigha, katha and cottah zero times and works in decimals, so the figure is official usage rather than law. Two consequences follow. A Kolkata listing in cottah means this 720, and a “3 cottah plot” is 2,160 ft², about 200.67 m², whatever the broker rounds it to. And a bigha here is 33.058 decimal, not the 33 that is usually printed; 33 decimal is 14,374.8 ft², which is 25 ft² short of twenty katha. Bangladesh's Ministry of Land publishes the same 720 and the same 20-katha ladder, and its own table carries the same 33-decimal rounding.
Assam has two kathas, and the one aggregators print is the smaller one. The same 1900 manual that gives the Bengal measure gives the Assam measure first: 144 ft² to the lessa, 20 lessa to the katha, 5 katha to the bigha. The bigha is the same 14,400 ft² as Bengal's; the katha is 2,880 ft², four times the Bengal figure, because five of them fill the bigha instead of twenty. The manual says the Bengal measure was used in the Surma Valley districts, of which the Indian part is today's Barak Valley around Silchar. Which ladder Cachar, Karimganj and Hailakandi use in their records now could not be confirmed from any modern Assam source, and this page labels the Barak row with that date. A Guwahati plot quoted at 720 a katha has been shrunk to a quarter of its size by a converter that knew only Bengal.
Bihar publishes its katha as approximate and says it varies, so it is graded that way here. The Bihar Revenue Glossary gives the katha as “approx. 1361 sq ft in Patna and around” and the bigha only as “approx. 20 Kattha”, and says in terms that the square-foot measurement varies from region to region. This page uses 1,361.25, which is a twentieth of the 27,225 ft² pucca bigha, because that is the arithmetic the rounded 1361 came from; the 27,220 that circulates as a Bihar bigha is the department's rounded figure multiplied by 20 and appears in no Bihar document. Outside the Patna belt the district figures in circulation (3,267 for Bettiah, 1,742.4 for Chhapra, 1,901.25 for Hajipur) trace to one uncited encyclopedia article, and two aggregators give opposite answers for Hajipur. Bihar's record is kept in decimal and acre, so the dependable number is on the khatian, not on this page.
Numbers you will meet that are wrong. 1 katha = 1,000 ft² appears against Kolkata plots and belongs to no ladder: twenty of them make a 20,000 ft² bigha that no government prints, and it overstates a 720 ft² katha by 39%. A Kolkata katha of 1,361 or 1,440 ft² is the Patna figure, or the Bengal bigha divided by ten, crossing the state line. 1 katha = 2,880 ft² in Silchar, or 720 in Guwahati, is the two Assam ladders swapped, an error of four times either way. 1 katha = 66.89 m² is fine as a rounding but 1 katha = 67 m² on a ten-katha deed invents 1.1 m²; the exact figure is 66.8901888. 1 kattha = 338.63 m² for Nepal is arithmetic on 3,645 ft² and the government book prints 338.62, a difference in the fourth figure that only matters when a page claims both to be exact. And a page that says 1 katha = 720 ft² in Jharkhand is quoting West Bengal: the Ranchi settlement survey never used the word bigha as a land unit at all.
Exact by definition: 1 ft = 0.3048 m, so 1 ft² = 0.09290304 m²
(NIST Handbook 44, Appendix C; the international foot has been the only U.S. foot since 1 January 2023,
85 FR 62698); 1 gaj = 1 yd² = 9 ft²; 1 acre = 43,560 ft²; 1 decimal = 1/100
acre = 435.6 ft². Every metric, gaj, acre and decimal figure on this page follows from those
and from the katha you chose, with no rounding until the screen runs out of digits.
West Bengal and Assam, both valleys: Manual of Mensuration and Surveying for Mandals and Patwaris
in Assam, Shillong 1900, section 30(a) “Assam measure (officially used)”: 144 sq ft = 1 lessa,
20 lessa = 1 katha, 5 katha = 1 bigha; and section 30(b) “Bengal measure”: 20 katha of 720 sq
ft = 1 bigha = 1,600 sq yd, “used in the Surma Valley districts”. Read from an Internet Archive
snapshot of the Assam Revenue and Disaster Management Department's own URL, because the host did not
respond; its cross-checks close exactly (1 acre = 3 bigha 8 chatak on the Bengal ladder, 3 bigha
2½ lessa on the Assam one). This is the same document and citation the bigha page rests on. A
government publication and not a statute: neither the West Bengal Land Reforms Act, 1955 nor Assam's
2015 agricultural land Act defines the unit.
Bangladesh: Ministry of Land, Government of Bangladesh, “Standard Units of Land Measurement in
Bangladesh”: 1 Katha = 720 Sq Feet, 20 Katha = 1 Bigha, 1 Acre = 60.5 Kattah, all of which close
exactly against 43,560. A ministry table, not a statute; Bangladesh is metric by law.
Nepal: Government of Nepal, Ministry of Federal Affairs and General Administration, with PLGSP,
Reference Book on Building By-laws and Building Permit System, June 2023, section 1.1.2 (page 5), read
here from the ministry's own PDF: “6772.41 sq.m = 1 Bigha = 20 Katha = 72900 sq.ft” and
“338.62 sq/m = 1 Katha = 20 Dhur = 3645 sq.ft”. This page computes from the 3,645 ft²
on the international foot, which gives 338.6316 m²; the book's metric figures are its own
roundings. Terai and Inner Madhesh only; the hills use the ropani, and the same table gives it as
5,476 sq ft.
Bihar: Bihar Revenue Glossary, Department of Revenue and Land Reforms (approved 13.10.2025),
“Kattha: approx. 1361 sq ft in Patna and around”, “varies from region to region”,
“Bigha: approx. 20 Kattha”. The 1,361.25 used here is 27,225 / 20 and is stated as convention
consistent with that glossary, not as a figure Bihar prints.
Madhya Pradesh: commonly quoted, no primary source found. Twenty katha of 600 sq ft is what
Indore and Gwalior brokers say; the M.P. Land Revenue Code, 1959 defines no unit of area and the khasra
is in hectares. The three refusals (Bihar beyond Patna, Jharkhand, North Bengal) are explained on the
widget itself and in full on the bigha page, whose sources they share: the Bihar glossary above, J.
Reid's Final Report on the Survey and Settlement Operations in the District of Ranchi, 1902‑1910,
and the absence of any West Bengal government publication on a North Bengal bigha.
Worked example
A Kolkata listing says 3 cottah. How many square feet is that, and what would the same plot be in Guwahati?
- On the Bengal measure a bigha is 14,400 ft² and holds 20 katha, so a katha is 720 ft², exactly 80 gaj. 3 × 720 = 2,160 ft².
- 2,160 × 0.09290304 = 200.670566 m², and 2,160 ÷ 9 = 240 gaj. In acres it is 2,160 ÷ 43,560 = 0.0496, which is 4.959 decimal, the unit the West Bengal record is actually kept in.
- The same three katha in the Brahmaputra Valley would be 3 × 2,880 = 8,640 ft², because Assam puts five katha to the same 14,400 ft² bigha. The 2,160 ft² Kolkata plot is 0.75 of a Guwahati katha.
2,160 ft², 200.67 m², 240 gaj, 0.15 of a Bengal bigha. The 720 figure is the 1900 survey manual's Bengal measure and the same number Bangladesh's Ministry of Land publishes; no West Bengal statute repeats it, and the deed will carry decimals. Read the same listing as a Guwahati one and it is four times the land.
13 values on this page were driven in a browser and compared with independently derived figures on 2026-09-09 (2258 values across 188 calculators site-wide).
Questions
How many square feet is 1 katha?
It depends on the bigha it sits under. In Kolkata and across south Bengal, and in Bangladesh, a katha is 720 ft² (80 gaj, 66.89 m²), a twentieth of a 14,400 ft² bigha. In Assam's Brahmaputra Valley it is 2,880 ft², a fifth of the same bigha. Bihar's own glossary gives the Patna katha only as about 1,361 ft² and says it varies by region. In the Nepal Terai a kattha is 3,645 ft². There is no single answer, and a page that gives one has guessed the region.
Is 1 katha 1,000 square feet?
No ladder produces that figure. Twenty of them would make a 20,000 ft² bigha that no government publishes. Against the Bengal katha of 720 ft² it is 39% too large; against the Patna figure of about 1,361 it is 27% too small. Where a listing says 1,000, ask which record the number came from, because it did not come from a survey manual or a revenue glossary.
How many katha are in a bigha, and how many in an acre?
Twenty katha to the bigha in Bengal, Bihar, Bangladesh and Nepal; five in the Brahmaputra Valley of Assam. An acre is 60.5 Bengal katha (43,560 ÷ 720), 15.125 Assam Valley katha, about 32 Patna katha and 11.95 Nepal kattha. All four come from one acre of 43,560 ft²; what changes is the katha.