Demographic features of the population of South Korea include population density, ethnicity, education level, health of the populace, economic status, religious affiliations, and other aspects of the population.
In June 2012, South Korea's population reached 50 million, and by the end of 2016, South Korea's population peaked at about 51 million people. However, in recent years the total fertility rate (TFR) of South Korea has plummeted, leading some researchers to suggest that if current trends continue, the country's population will shrink to approximately 28 million people by the end of the 21st century.
In 2018, fertility in South Korea became a topic of international debate after only 26,500 babies were born in October and an estimated 325,000 babies for the year, causing the country to achieve the lowest birth rate in the world. In a further indication of South Korea's dramatic decline in fertility, in 2020 the country recorded more deaths than births, resulting in a population decline for the first time since modern records began.
Analysts have attributed South Korea's population decline resulting from low birth rates to the country's high economic inequality; including the high cost of living, low wages for an OECD member country, lack of job opportunities, as well as rising housing in-affordability. Many South Koreans have termed their country "Hell Joseon" as a result, and the last two generations has considered themselves "Sampo" and "N-po" respectively. South Korea also has the highest suicide rate in the OECD and the wider developed world.
In South Korea, a variety of different Asian people had migrated to the Korean Peninsula in past centuries, however few have remained permanently. South Korea despite formerly being a highly homogenous nation, has in recent decades become home to a number of foreign ethnicities, whereas North Korea has not experienced this trend. Both North Korea and South Korea equate nationality or citizenship with membership in a single, homogenous ethnic group and politicized notion of "race.