Land Size Converter: Acres, Decimals, Hectares, Plots
Updated 3 November 2026 · Land & Property editorial team
One acre is 100 decimals, 43,560 square feet, about 4,047 square metres or 0.4047 hectares. A decimal is 435.6 square feet, about 40.5 square metres. A 50 by 100 foot plot is 5,000 square feet, which is 11.5 decimals by arithmetic, though many sellers quote 12 or 12.5. Use the converter below, then check any quoted size against the deed plan.
- 1 acre
- 100 decimals, 43,560 sq ft, 4,046.86 sq m, 0.4047 ha
- 1 decimal
- 435.6 sq ft, about 40.47 sq m
- 1 hectare
- 10,000 sq m, about 2.471 acres, about 247 decimals
- 50 x 100 ft plot
- 5,000 sq ft, about 464.5 sq m, about 11.5 decimals
- 1 square mile
- 640 acres, about 259 hectares
How do I convert acres to decimals, hectares and square metres?
Type a number into the converter at the top of this page, pick the unit it is in, and it shows the same area in the other units. The tool does one thing: it multiplies by fixed factors. It does not know your plot, your title or your seller. The factors below are the ones it uses, so you can check any answer by hand.
The international acre is exactly 43,560 square feet, which is about 4,046.86 square metres or 0.40469 hectares (Wikipedia, "Acre"). A decimal is one hundredth of an acre, so it is 435.6 square feet or about 40.47 square metres (Wikipedia, "Decimal (unit)"). From those two facts everything else follows.
| Unit | Acres | Decimals | Square feet | Square metres (about) |
|---|---|---|---|---|
| 1 decimal | 0.01 | 1 | 435.6 | 40.5 |
| 12.5 decimals (one eighth of an acre) | 0.125 | 12.5 | 5,445 | 506 |
| 25 decimals (a quarter of an acre) | 0.25 | 25 | 10,890 | 1,012 |
| 1 acre | 1 | 100 | 43,560 | 4,047 |
| 1 hectare | 2.471 | 247.1 | 107,639 | 10,000 |
| 1 square mile | 640 | 64,000 | 27,878,400 | 2,589,988 |
To go from square metres to decimals, divide by 40.47. To go from hectares to decimals, multiply by 247.1. To go from square feet to square metres, multiply by 0.0929.
How many decimals is a 50 by 100 plot, and why do sellers say 12.5?
A plot of 50 by 100 feet is 5,000 square feet. Divide by 435.6 and you get 11.48 decimals, which rounds to 11.5. That is the arithmetic. In everyday selling, many people treat a 50 by 100 plot as one eighth of an acre, which is 12.5 decimals or 5,445 square feet. The two figures are about 445 square feet apart, roughly 41 square metres.
You can see both habits in our own listings (Land & Property listings, Nov 2026). One Kira Nsasa listing describes a 50 by 100 ft plot as "12 decimals" at UGX 85 million. A Kyanja listing describes a 100 by 100 ft plot as "25 decimals" at UGX 520 million. A true 100 by 100 ft plot is 10,000 square feet, which is 22.96 decimals, so the advert rounds up by about two decimals.
This is not fraud by itself. It is a trade shorthand. But it changes the price per decimal. At UGX 85 million, 12 decimals is about UGX 7.08 million a decimal, while 11.48 decimals is about UGX 7.41 million a decimal. The fix is simple: ask which figure the seller means, and write the size in square feet or square metres into the sale agreement as well. Our page on what is a decimal of land in Uganda goes through this, and 50 by 50 and 100 by 100 plots in Uganda: size, cost, use covers the other common plot shapes.
What is the square miles note for old mailo land?
Large old mailo parcels were measured in square miles, and some are still advertised that way. One square mile is 640 acres, which is about 259 hectares. Two of our current farmland listings use the unit: one offers "1 square mile" as 640 acres in Nakasongola, and another offers "2 square miles" as 1,280 acres (Land & Property listings, Nov 2026). Both give the acre figure beside the square-mile figure, which is the safe way to do it.
If an old title or advert gives only square miles, convert it to acres first, then to decimals or hectares. Multiply square miles by 640 for acres, by 64,000 for decimals, and by 259 for hectares. The converter has square miles as an input for this reason. A square mile is also a whole block shape in some old surveys, so ask a surveyor whether the figure on the paper is an area or a block name. For the tenure side, read what is mailo land.
When should I not trust a converter?
A converter turns one number into another. It cannot tell you whether the first number is right. Three cases need care.
- The advert is rounded. "A quarter of an acre" and "25 decimals" are the same on paper, but a plot measured on the ground may be 22 or 27. Only a survey settles it.
- The title shows a different unit. Deed plans often give hectares or square metres. Convert that figure and compare it with the advert. A gap of more than a decimal or two needs an explanation.
- The shape matters. Two plots with the same area can be a usable rectangle or a narrow strip. Area alone does not show road frontage or boundaries.
Use the converter to check numbers, then use a registered surveyor and the deed plan to check the land. Our guide to how many plots are in an acre shows how layout, roads and access take space out of the raw total.
How do I compare prices once the sizes are in the same unit?
Adverts quote a whole-plot price, a price per decimal or a price per acre. Convert them all to one unit before you compare. Our snapshot shows why. A Bunga plot of 25 decimals is advertised at UGX 820 million, which is about UGX 32.8 million a decimal or about UGX 3.28 billion an acre. A Kira Nsasa plot of 12 decimals at UGX 85 million is about UGX 7.1 million a decimal (Land & Property listings, Nov 2026). These are asking prices on single adverts, not market prices, and the areas are very different.
Farmland is usually priced per acre, plots by the whole plot or per decimal. Mixing the two is the commonest comparison mistake. Read price per decimal vs price per acre before you rank offers, and see land prices in Uganda for the wider picture. If you are paying by instalments, the size you write into the agreement fixes what each payment buys, so see land on installments.
Can I put this converter on my own site?
If you run a property site, a surveyor's page or an agency page and want the same converter, ask our team and we will tell you whether an embed is available for your page. The conversion factors on this page are public arithmetic, so you are free to check them against any other source. Agents who want to list plots accurately can start from the size in square feet, add the decimal figure and say which convention they use.
Ready to see land in person? Browse plot listings or book an escorted site visit, and have the surveyor measure the plot with you.
Frequently asked questions
How many hectares is an acre?
One acre is 0.4047 hectares (0.40468564 exactly, from 43,560 square feet). Put the other way, one hectare is about 2.471 acres, or about 247 decimals. The hectare is 10,000 square metres, which is why deed plans in square metres convert easily to hectares by dividing by 10,000.
How many square metres is one decimal?
One decimal is about 40.47 square metres, or 435.6 square feet. It is one hundredth of an acre. So 25 decimals is about 1,012 square metres, and 100 decimals, one full acre, is about 4,047 square metres.
How many decimals is a 50 by 100 plot?
By arithmetic a 50 by 100 foot plot is 5,000 square feet, which is about 11.5 decimals. Many sellers call it 12 or 12.5 decimals, because 12.5 decimals is one eighth of an acre. Ask the seller which figure they mean and write the size in square feet into the agreement.
How many acres is one square mile?
One square mile is 640 acres, which is about 259 hectares or 64,000 decimals. Old mailo parcels and some farmland adverts still use square miles, so convert to acres first and then to the unit you compare prices in.
Is the converter a replacement for a survey?
No. It converts numbers, it does not measure land. The size in an advert is a claim. The deed plan and a surveyor measuring on the ground are the evidence, and the size you confirm should go into the sale agreement.
Sources
- Acre, Wikipedia (accessed 2026-11)
- Decimal (unit), Wikipedia (accessed 2026-11)