Convert Acre to Square Kilometre
1 acre = 0.004046856 square kilometre (km²). For example, 10 acre = 0.04046856 square kilometre and 100 acre = 0.4046856 square kilometre. Type any value below to convert acre to square kilometre both ways — it runs entirely in your browser.
Quick answer: Acre to Square Kilometre
1 Acre = 0.004046856 Square Kilometre (ac → km²). To convert acre to square kilometre, multiply by 0.004046856. To convert square kilometre to acre, multiply by 247.1054. The converter at the top does this instantly and both ways; the sections below give the formula, worked examples, a full conversion chart and answers to the most common acre-to-square kilometre questions.
How to convert Acre to Square Kilometre
To convert acre to square kilometre, multiply the number of acre by the conversion factor 0.004046856, because 1 ac = 0.004046856 km². The conversion is linear, so the same factor works for any value — whole numbers, decimals or fractions. For the reverse direction, 1 km² = 247.1054 ac, so you divide by 0.004046856 (or multiply by 247.1054) to turn square kilometre back into acre.
km² = ac × 0.004046856 ·
ac = km² × 247.1054
- Write down the value you want to convert, in acre.
- Multiply it by 0.004046856.
- The result is the same area/length/quantity expressed in square kilometre.
Acre to Square Kilometre — worked examples
Each row shows the exact arithmetic so you can follow the conversion step by step. For example, 5 acre is 0.02023428 square kilometre because 5 ac × 0.004046856 = 0.02023428 km².
| Acre | Calculation | Square Kilometre |
|---|---|---|
| 1 ac | 1 ac × 0.004046856 = 0.004046856 km² | 0.004046856 km² |
| 2 ac | 2 ac × 0.004046856 = 0.008093713 km² | 0.008093713 km² |
| 3 ac | 3 ac × 0.004046856 = 0.01214057 km² | 0.01214057 km² |
| 5 ac | 5 ac × 0.004046856 = 0.02023428 km² | 0.02023428 km² |
| 7 ac | 7 ac × 0.004046856 = 0.02832799 km² | 0.02832799 km² |
| 10 ac | 10 ac × 0.004046856 = 0.04046856 km² | 0.04046856 km² |
| 12 ac | 12 ac × 0.004046856 = 0.04856228 km² | 0.04856228 km² |
| 15 ac | 15 ac × 0.004046856 = 0.06070285 km² | 0.06070285 km² |
| 20 ac | 20 ac × 0.004046856 = 0.08093713 km² | 0.08093713 km² |
| 25 ac | 25 ac × 0.004046856 = 0.1011714 km² | 0.1011714 km² |
| 50 ac | 50 ac × 0.004046856 = 0.2023428 km² | 0.2023428 km² |
| 100 ac | 100 ac × 0.004046856 = 0.4046856 km² | 0.4046856 km² |
Common Acre to Square Kilometre conversions
These are the acre-to-square kilometre values people look up most often. Every figure is computed from the exact factor, so you can rely on them for quick reference:
- 1 acre = 0.004046856 square kilometre
- 2 acre = 0.008093713 square kilometre
- 2.5 acre = 0.01011714 square kilometre
- 3 acre = 0.01214057 square kilometre
- 4 acre = 0.01618743 square kilometre
- 5 acre = 0.02023428 square kilometre
- 6 acre = 0.02428114 square kilometre
- 7 acre = 0.02832799 square kilometre
- 8 acre = 0.03237485 square kilometre
- 9 acre = 0.03642171 square kilometre
- 10 acre = 0.04046856 square kilometre
- 12 acre = 0.04856228 square kilometre
- 15 acre = 0.06070285 square kilometre
- 20 acre = 0.08093713 square kilometre
- 25 acre = 0.1011714 square kilometre
- 30 acre = 0.1214057 square kilometre
- 50 acre = 0.2023428 square kilometre
- 75 acre = 0.3035142 square kilometre
- 100 acre = 0.4046856 square kilometre
- 200 acre = 0.8093713 square kilometre
- 500 acre = 2.023428 square kilometre
- 1000 acre = 4.046856 square kilometre
Acre to Square Kilometre conversion chart (both directions)
The chart below converts acre to square kilometre and square kilometre to acre side by side, so it works whichever way you need. 1 acre = 0.004046856 square kilometre, and 1 square kilometre = 247.1054 acre.
| Acre → Square Kilometre | Square Kilometre → Acre |
|---|---|
| 0.25 ac = 0.001011714 km² | 0.25 km² = 61.77635 ac |
| 0.5 ac = 0.002023428 km² | 0.5 km² = 123.5527 ac |
| 1 ac = 0.004046856 km² | 1 km² = 247.1054 ac |
| 2 ac = 0.008093713 km² | 2 km² = 494.2108 ac |
| 3 ac = 0.01214057 km² | 3 km² = 741.3161 ac |
| 4 ac = 0.01618743 km² | 4 km² = 988.4215 ac |
| 5 ac = 0.02023428 km² | 5 km² = 1,235.527 ac |
| 6 ac = 0.02428114 km² | 6 km² = 1,482.632 ac |
| 7 ac = 0.02832799 km² | 7 km² = 1,729.738 ac |
| 8 ac = 0.03237485 km² | 8 km² = 1,976.843 ac |
| 9 ac = 0.03642171 km² | 9 km² = 2,223.948 ac |
| 10 ac = 0.04046856 km² | 10 km² = 2,471.054 ac |
| 12 ac = 0.04856228 km² | 12 km² = 2,965.265 ac |
| 15 ac = 0.06070285 km² | 15 km² = 3,706.581 ac |
| 20 ac = 0.08093713 km² | 20 km² = 4,942.108 ac |
| 25 ac = 0.1011714 km² | 25 km² = 6,177.635 ac |
| 30 ac = 0.1214057 km² | 30 km² = 7,413.161 ac |
| 40 ac = 0.1618743 km² | 40 km² = 9,884.215 ac |
| 50 ac = 0.2023428 km² | 50 km² = 12,355.27 ac |
| 75 ac = 0.3035142 km² | 75 km² = 18,532.9 ac |
| 100 ac = 0.4046856 km² | 100 km² = 24,710.54 ac |
| 150 ac = 0.6070285 km² | 150 km² = 37,065.81 ac |
| 200 ac = 0.8093713 km² | 200 km² = 49,421.08 ac |
| 250 ac = 1.011714 km² | 250 km² = 61,776.35 ac |
| 500 ac = 2.023428 km² | 500 km² = 123,552.7 ac |
| 1000 ac = 4.046856 km² | 1000 km² = 247,105.4 ac |
Acre vs Square Kilometre: which is bigger?
A square kilometre is the larger unit: one square kilometre equals 247.1054 acres. Put another way, you need 247.1054 acres to make a single square kilometre.
What is a Acre? History, origin and usage
Ac is simply the abbreviation for the acre, one of the oldest English land measures, whose name comes through Norman French from a root meaning 'cultivated field'. It was historically the area a team of eight oxen could plough in a day, fixed as one chain by one furlong.
The acre remains a statutory unit in the United States and across the Commonwealth, and is a main unit for Indian agricultural land alongside the bigha and hectare. It is used for farms, estates and large plots worldwide.
One acre is 4,840 square yards or 43,560 square feet, about 0.405 hectare, and roughly nine-tenths the size of an American football field. It equals 8 kanal or 160 marla in the Punjab system.
What is a Square Kilometre? History, origin and usage
The square kilometre is an SI-based unit of area equal to a square one kilometre on each side. It became the natural large-area metric unit once the kilometre was adopted for long distances.
It is used for the areas of cities, districts, countries, lakes and other large regions on maps and in geography and statistics. National and regional land areas are almost universally reported in square kilometres.
One square kilometre equals 100 hectares or 1,000,000 square metres, and is about 0.386 square mile. For scale, the entire Vatican City covers only about half a square kilometre.
Convert 1 Acre to other units
It can help to see a acre next to the other units it is commonly compared with. One acre (ac) is equal to:
| 1 Acre equals | Unit |
|---|---|
| 4,840 gaj | Gaj |
| 160 marla | Marla |
| 8 kanal | Kanal |
| 1 killa | Killa |
| 0.04 murabba | Murabba |
| 100 decimal | Decimal |
| 100 cent | Cent |
| 40 guntha | Guntha |
| 1 ac | Acre |
| 0.4046856 ha | Hectare |
| 43,560 ft² | Square Foot |
| 4,840 yd² | Square Yard |
| 4,046.856 m² | Square Metre |
| 40,468,560 cm² | Square Centimetre |
| 4,046,856,000 mm² | Square Millimetre |
| 6,272,640 in² | Square Inch |
| 0.004046856 km² | Square Kilometre |
| 40.46856 are | Are |
| 4.046856 daa | Decare |
| 0.0015625 mi² | Square Mile |
| 4,840 yd² | Square Yard |
| 43,560 ft² | Square Foot |
| 0.4046856 ha | Hectare |
| 1,440 karam² | Square Karam |
| 18.15 ground | Ground |
| 302.5 lessa | Lessa |
| 968 chatak | Chatak |
| 0.75625 pura | Pura |
Convert 1 Square Kilometre to other units
One square kilometre (km²) is equal to:
| 1 Square Kilometre equals | Unit |
|---|---|
| 1,195,990 gaj | Gaj |
| 39,536.86 marla | Marla |
| 1,976.843 kanal | Kanal |
| 247.1054 killa | Killa |
| 9.884215 murabba | Murabba |
| 24,710.54 decimal | Decimal |
| 24,710.54 cent | Cent |
| 9,884.215 guntha | Guntha |
| 247.1054 ac | Acre |
| 100 ha | Hectare |
| 10,763,910 ft² | Square Foot |
| 1,195,990 yd² | Square Yard |
| 1,000,000 m² | Square Metre |
| 10,000,000,000 cm² | Square Centimetre |
| 1,000,000,000,000 mm² | Square Millimetre |
| 1,550,003,000 in² | Square Inch |
| 10,000 are | Are |
| 1,000 daa | Decare |
| 0.3861022 mi² | Square Mile |
| 247.1054 ac | Acre |
| 1,195,990 yd² | Square Yard |
| 10,763,910 ft² | Square Foot |
| 100 ha | Hectare |
| 355,831.7 karam² | Square Karam |
| 4,484.963 ground | Ground |
| 74,749.38 lessa | Lessa |
| 239,198 chatak | Chatak |
| 186.8734 pura | Pura |
Tips for converting Acre to Square Kilometre
- To go from acre to square kilometre, multiply by 0.004046856; to go back, divide by 0.004046856 (or multiply by 247.1054).
- For a quick mental estimate, remember that 1 acre ≈ 0.004046856 square kilometre, so 10 acre ≈ 0.04046856 square kilometre.
- The converter above keeps full precision; the tables round for readability, so use the tool for exact figures.
- Both fields update live as you type — change either side to convert in that direction.
How to use this Acre to Square Kilometre converter
Type a number into the Acre field and the equivalent in Square Kilometre appears instantly — there is no “convert” button to press and nothing is sent to a server, so it works offline once the page has loaded and is safe for any data. You can also type into the Square Kilometre field to convert the other way (square kilometre to acre). Use the swap control to flip the two units, and copy the result with a single click. Because the calculation runs in your browser with full floating-point precision, the converter is more exact than the rounded figures shown in the reference chart above — use the chart for quick look-ups and the tool for precise work.
Accuracy and method
Every figure on this page — the formula, the worked examples, the conversion chart and the “convert to other units” tables — is computed from a single verified conversion factor (1 ac = 0.004046856 km²), never copied from a hand-typed lookup table that could drift. That factor is derived from each unit’s definition in terms of a common base unit, and an automated check re-verifies all of the site’s factors on every update, so the numbers here stay correct over time. This matters for acre-to-square kilometre conversions because a small rounding error in a published table compounds quickly at larger quantities; computing from the exact factor avoids that.
Sources
- NIST Special Publication 811 — Guide for the Use of the SI — publishes the exact metric equivalents of the customary units. The inch, foot, yard and mile are defined exactly in metres by the 1959 international yard-and-pound agreement, so every imperial figure on this page is exact, not rounded.
- BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.
Indian land units can vary by state and local custom. This converter uses the most widely accepted standard value; always confirm against your local revenue records (patwari / tehsil) for legal transactions.
Frequently asked questions
- How many square kilometre are in 1 acre?
- 1 acre = 0.004046856 square kilometre (km²). To convert any number of acre to square kilometre, multiply by 0.004046856.
- How do I convert acre to square kilometre?
- Multiply the number of acre by 0.004046856. For example, 10 acre = 10 × 0.004046856 = 0.04046856 square kilometre, and 25 acre = 0.1011714 square kilometre.
- How many acre are in 1 square kilometre?
- 1 square kilometre = 247.1054 acre. So to convert square kilometre back to acre, multiply by 247.1054.
- What is the formula to convert acre to square kilometre?
- square kilometre = acre × 0.004046856. The reverse formula is acre = square kilometre × 247.1054.
- How much is 100 acre in square kilometre?
- 100 acre = 0.4046856 square kilometre. (And 1000 acre = 4.046856 square kilometre.)
- Which is bigger, a acre or a square kilometre?
- A square kilometre is larger: 1 square kilometre = 247.1054 acre.
- Is this acre to square kilometre converter accurate?
- Yes — every value is computed from the exact 0.004046856 km² per ac factor (not rounded look-up tables), and the factors are re-verified automatically on every update.
- Can I convert square kilometre to acre too?
- Yes. The converter works both ways — enter a value in either field. 1 square kilometre = 247.1054 acre.