Mercer is a very small borough located in the state of Pennsylvania. With a population of 1,955 people and three associated neighborhoods, Mercer is the 651st largest community in Pennsylvania. Much of the housing stock in Mercer was built prior to World War II, making it one of the older and more historic boroughs in the country.

Mercer’s overall crime rate ranks among the lowest in the nation, making it a very safe place to live.

Being a small borough, Mercer does not have a public transit system used by locals to get to and from work.

In terms of college education, Mercer is nearly on par with the US average for all cities of 21.84%: 18.88% of adults 25 and older in Mercer have a bachelor's degree or advanced degree.

The per capita income in Mercer in 2018 was $34,621, which is middle income relative to Pennsylvania and the nation. This equates to an annual income of $138,484 for a family of four. However, Mercer contains both very wealthy and poor people as well.

The people who call Mercer home describe themselves as belonging to a variety of racial and ethnic groups. The greatest number of Mercer residents report their race to be White, followed by Asian. Important ancestries of people in Mercer include German, Irish, English, Italian, and Scots-Irish.

The most common language spoken in Mercer is English. Other important languages spoken here include Polish and French.