Population Density Calculator
By Santaji GadepatilinUpdated October 27, 2026
Population density is the number of individuals per unit area. It is used in ecology, urban planning and geography.
How to use the population density calculator
Enter the population and the area. Density per km², per square mile and per hectare are calculated.
Example
1,250,000 people in 450 km²:
- 2,778 per km²
- 7,194 per square mile
- 27.8 per hectare
Population density examples
| Place | Approximate density |
|---|---|
| World (land area) | about 60 per km² |
| India | about 480 per km² |
| United Kingdom | about 280 per km² |
| United States | about 37 per km² |
| Australia | about 3–4 per km² |
| Singapore | about 8,000 per km² |
| Monaco | about 19,000 per km² |
Figures are approximate and change with population estimates.
Density units
| Unit | Equals |
|---|---|
| 1 per km² | 2.59 per square mile |
| 1 per hectare | 100 per km² |
| 1 per acre | 247 per km² |
Ecological density
In ecology, population density helps compare species abundance between habitats:
- Crude density: individuals per total area.
- Ecological density: individuals per area of suitable habitat.
Plant ecologists often count individuals in quadrats (for example 1 m²) and scale up.
Physiological density
For countries, physiological density divides population by arable land only. Egypt has a moderate crude density but a very high physiological density because most people live along the Nile.
Frequently asked questions
How is population density calculated?
Divide the number of individuals by the area they occupy.
How do I convert per km² to per square mile?
Multiply by 2.59.
Is density the same everywhere in an area?
No — it is an average. Cities and habitats are often much denser in some places than others.
How do I calculate population density?
Divide the population by the area. 1.25 million people on 450 km² is about 2,778 per km².
How do I convert per km² to per square mile?
Multiply by 2.59.