Acres to Square kilometres Converter
Convert acres (ac) to square kilometres (km²) instantly. Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
Result
- Square kilometres
- 0.004047 km²
How to use the acres to square kilometres converter
- Enter the acres (ac).
- The results update as you type, or press Calculate.
- Read the square kilometres first, then the supporting figures below it.
Formula
Square kilometres = acres × 0.0040468564
Worked example
For example, with these inputs:
- Acres (ac): 1
the calculator returns:
- Square kilometres: 0.004047 km²
Acres to Square kilometres table
| Acres | Square kilometres |
|---|---|
| 1 ac | 0.004047 km² |
| 2 ac | 0.008094 km² |
| 5 ac | 0.020234 km² |
| 10 ac | 0.040469 km² |
| 20 ac | 0.080937 km² |
| 25 ac | 0.101171 km² |
| 50 ac | 0.202343 km² |
| 100 ac | 0.404686 km² |
| 250 ac | 1.0117 km² |
| 500 ac | 2.0234 km² |
| 1,000 ac | 4.0469 km² |
About this conversion
Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
Frequently asked questions
How many square kilometres are in one acre?
1 ac = 0.004047 km².
How do I convert ac to km²?
Square kilometres = acres × 0.0040468564.