Ground to Square Feet — the Chennai plot unit, graded
One ground is 2,400 ft², 222.97 m², 266.67 sq yd and 5.51 cents by Chennai convention; 18.15 to the acre. Where the figure comes from, and the wrong numbers.
One ground is 2,400 ft², 222.967 m² and 266.67 square yards by Chennai convention: 5.51 cents, 18.15 to the acre. The figure is printed in one Chennai Corporation tax line and defined by no statute, and the page says which of its numbers rest on which.
Plots in Chennai and the districts around it are listed in grounds: half a ground, one ground, one and a half, two, three. The conversion everyone uses is 1 ground = 2,400 ft², so a 1.5‑ground plot is 3,600 ft² and 334.45 m². Once the 2,400 is granted, everything else on this page is exact arithmetic on the international foot.
What is not granted by any rule is the 2,400 itself. No Tamil Nadu act, rule or notification this page could read defines a ground. The one government document found that prints the figure is a rate line in Greater Chennai Corporation's method of property tax assessment, which prices vacant land “per 2400 Sq.feet (One Ground)”. That is a government using the market's unit, not fixing it, and the page grades the ground accordingly: a convention with one official use.
The converter takes an amount in any of the exact units or in grounds, puts the result beside cent, acre, hectare and gaj, and refuses the three things people ask it to do with the word “ground” that no source supports.
| Grounds — convention | — |
|---|---|
| Square feet | — |
| Square metres | — |
| Square yards (gaj) | — |
| Cent — exact | — |
| Acre · hectare | — |
| As a plot | — |
| How good is the ground figure | — |
The ground is a convention, and the government document that prints it is a tax rate, not a definition. Greater Chennai Corporation's property tax method fixes the annual value of vacant land at a rent “per 2400 Sq.feet (One Ground)”. That is the corporation counting in the unit the city already counts in. It does not say a ground is 2,400 ft² anywhere else, and no Tamil Nadu act or rule read for this page defines the word at all. The Government of India's Glossary of Revenue Terms, compiled with every state, does not contain the unit, and its Tamil Nadu chapter shows the record of rights recording extent in hectares and ares. So the honest grade is the one the widget prints: a convention, uniform enough across Chennai to be useful, with one official use behind it. If your document states its own area in square feet or square metres, that figure governs and the ground is a description of it.
Against the exact units the arithmetic is ugly, and the ugliness is the evidence. A cent is exactly one hundredth of an acre, 435.6 ft², so a ground is 5.5096 cents, not the 5.5 some tables print. An acre is 18.15 grounds. A hectare is 44.85. In square metres a ground is 222.967296 exactly, because 2,400 × 0.09290304 is, and in square yards it is 266.667, which is 2,400 divided by nine. None of these is a round number because a ground is not a fraction of an acre or of anything else; it is a plot size that hardened into a unit. The cent, by contrast, is a definition, and this site keeps the two apart on its cent page for the same reason.
A 60 by 40 plot is one ground exactly, which is arithmetic and not a history. 60 × 40 = 2,400, and so does 80 × 30 and 120 × 20. Chennai layout brochures list all three as ground‑sized plots. It is tempting to read the 60 by 40 as the origin of the figure, and no source read for this page says so; the page offers the coincidence and nothing more. What the sizes tell you is practical: half a ground is 1,200 ft², the size of a small independent house plot, and a listing that says “1.5 grounds” means 3,600 ft², 334.45 m², 400 square yards and 8.26 cents. The widget draws the entered area against those sizes so a figure quoted in square feet can be placed in the vocabulary the seller is using.
Listings say grounds; the deed, the guideline value and the tax bill say square feet or square metres. Tamil Nadu's guideline value, the floor price the registration department applies to stamp duty, is published per square foot for urban plots and per acre or hectare for agricultural land, and the schedule of property in a Chennai sale deed states its extent in square feet or square metres even when the same deed calls the plot “one ground” in the narrative. That is how the practice runs; it is not a rule this page can cite, and the registration portal itself refused connections from outside India while this was researched, so the description rests on the documents people post rather than on the department's own page. Practical consequence: to compare a price per ground with a guideline value per square foot, divide the price by 2,400, and to check a deed against a listing, multiply the grounds by 2,400 and expect the deed's figure to be a few square feet either side of it, because the surveyed plot is never exactly 60 by 40.
Numbers you will meet that are wrong. 1 ground = 2,500 ft² is a rounding to a nicer figure and is 4.2% high: on three grounds it invents 300 square feet. 1 ground = 200 m² is 10.3% low, a whole 23 square metres short on a single plot, and the encyclopedia figure of 203 m² (2,190 ft²) is nearly as far off and cites nothing that would justify it. 1 ground = 2,200 ft² circulates as the value in “older localities”; no government document, gazette or survey source read for this page supports a 2,200 ground anywhere, so the widget will not convert at it and says why. And a “ground” quoted in Kerala, Maharashtra or Gujarat, which several converter sites list, is a word the aggregators have carried across a state line: those states count in cents, ares, gunthas and square metres, and the page found no source for a ground of any size there.
Exact by definition, needing no source beyond the definitions: 1 ft =
0.3048 m, so 1 ft² = 0.09290304 m² (NIST Handbook 44 (2023), Appendix C; the
U.S. survey foot was retired by NIST and NOAA, 85 FR 62698, for use after 31 December 2022); 1 yd = 3 ft,
so 1 yd² = 9 ft², and the land gaj is that square yard; 1 acre = 43,560 ft²;
1 hectare = 10,000 m². Cent as 1/100 acre = 435.6 ft² is from the Glossary of Revenue
Terms, Department of Land Resources, Ministry of Rural Development, Government of India, Kerala chapter,
as cited in full on this site's cent page.
The ground at 2,400 ft² is Chennai market convention. The one government document read
that prints the figure is Greater Chennai Corporation, Property Tax Assessment, method of fixing annual
value for vacant land: “Rent per 2400 Sq.feet (One Ground) = Rs. 8.00 P.M.”, read from the
corporation's own page on 9 September 2026. It is a use of the unit in a rate line and not a
definition, and it is graded here as a government table entry for that reason and no higher. The
Government of India Glossary of Revenue Terms does not contain the ground; its Tamil Nadu chapter records
extent in hectares and ares. No Tamil Nadu statute, rule or CMDA regulation is cited for the figure
because none that states it was read.
Stated as convention with no citation, because none was found: that Chennai listings quote
grounds while deeds, guideline values and tax bills are in square feet or square metres; that 60 ×
40, 80 × 30 and 120 × 20 are the plot shapes sold as one ground (from developers' own
layout descriptions, not from any authority). The 2,200 ft² ground, the ground outside Tamil
Nadu and the ground floor of a building are not converted: the first two have no source, and the third
is not an area.
Worked example
A Chennai listing says 1.5 grounds. How many square feet, square metres and cents is that?
- By Chennai convention 1 ground = 2,400 ft², so 1.5 × 2,400 = 3,600 ft².
- 3,600 × 0.09290304 = 334.45 m²; 3,600 ÷ 9 = 400 square yards.
- A cent is exactly 435.6 ft², so 3,600 ÷ 435.6 = 8.26 cents, and 3,600 ÷ 43,560 = 0.0826 acre.
3,600 ft² (334.45 m², 400 yd², 8.26 cents, 0.0826 acre). Only the first step depends on the 2,400 ft² convention; the rest is exact.
7 values on this page were driven in a browser and compared with independently derived figures on 2026-09-09 (2414 values across 203 calculators site-wide).
Questions
How many square feet is one ground?
2,400 ft² by Chennai convention, which is 222.97 m², 266.67 square yards and 5.51 cents. No Tamil Nadu statute defines the ground; the one government document that prints the figure is a Greater Chennai Corporation property tax rate line.
How many grounds are in an acre?
18.15, because 43,560 ÷ 2,400 = 18.15. The number is not round because a ground is a plot size that became a unit, not a fraction of an acre. A hectare is 44.85 grounds.
Is a 60 × 40 plot one ground?
Yes: 60 × 40 = 2,400 ft², as do 80 × 30 and 120 × 20. That is arithmetic, not the origin of the unit; no source read for this page says where the 2,400 came from.