Enter the total number of people and the area in which those people live into the calculator. The calculator will evaluate and display the population density.

Population Density Formula

The following equation can be used to calculate the population density of an area.

D = P / A
  • Where D is the density
  • P is the population number
  • A is the area

In the case of population density, we use a total number of people per unit area. Normally in math, density is a mass or number per unit volume. When analyzing populations, volumes don’t make much sense to look at, so we use area.

Population Density Definition

A population density is defined as the total number of people per unit of area.

Population Density Example

How to calculate population density?

The following example problem outlines the steps required for calculating a population density.

First, determine a specific area that is to be analyzed. In this example, we will use the city of New York as the area.

As of 2019, the city contained 8.419 million people. Note that this is only the borough of New York City, and does not include the surrounding metropolitan area.

Next, determine the total area of the city. For this problem, New York City is found to have a total size of 302.6 square miles.

Finally, calculate the population density using the formula D = P/A = 8,419,000 / 302.6 = 27,822.20 people per square mile.

Population Density Units

In most cases, population density is present in the number of people per square mile, or the number of people per square kilometer.

These units can be expressed in per thousands of people when looking at very dense areas, such as New York, like the example above shows.

6 Things to Know About Population Denisty

1. Why is population density important?

Population density is a key metric in understanding not only the economics and logistics involved in an area but also the culture and the mindset of the people living there.

One example of this importance can be seen in urban planning. When engineers design bridges, sewage, and other infrastructure for areas, one of the essential design considerations is population density.

Knowing the population density allows the engineer to design the infrastructure to handle that population or rate of usage the infrastructure would see. Without this critical information, the engineer my design something that could fail under heavier than expected usage.

2. Can population density change?

A population density will change when the number of people living in an area increases or decreases.

If the population increases in an area, the population density will also increase. If the population decreases, the density will also decrease. This means that the population and density are directly dependent on one another. This can be seen from the equation above.

Another uncommon way population density can change is if the borders of an area are changed legally.

For example, if a town had an initial area of 20 square miles, but after some litigation, the town agrees to include another 1 square mile area in their borders, then the population density will change.

3. Does population density affect temperature and climate?

Population density can affect temperatures and climate. This can be seen on a global scale across the Earth in the last century.

As populations continue to increase, the global climate crisis has continued to worsen. The more people there are, the more natural resources are burned to support them. This leads to an increase in global temperatures.

This can also be seen on a smaller scale in cities. The denser the city, the higher the temperatures are compared to the surrounding areas. This is caused by excess heat exhaust from people heating and cooling their homes.

4. What population density levels are considered urban and what levels are considered rural?

According to the U.S. census bureau, urban areas must have a minimum of 1,000 people per square mile and at least 50,000 residents. Rural areas on the other hand are areas that have less than 500 people, or less than 2,500 people total.

5. What are the effects of low population density?

Having a low population density has both benefits and downsides.

Some of the benefits include; lower cost for land in the area since there are fewer people and therefore less demand, there is less congestion on roadways, less pollution, and fresher produce.

Some of the downsides of low population density are; less efficient productivity, longer commute times, less diversity of social groups, and lower wages.

All of these benefits and downsides would be reversed when looking at the high-density areas, i.e. the benefits would become downsides.

6. Where is population density the highest?

The highest density population areas in the world are all major cities, with the highest density being in Manilla, Philippines which has a population density of roughly 107,000 people per square mile.

In fact, the top three most dense places on Earth are all in the Philippines.