Once Łódź enjoyed impressive natural population growth – over 30 post-war years the city gained 300 thousand citizens! In 1976, as the narrator of the Polish Film Chronicle announced, an "800-thousandth baby of great Łódź" was born!

Łódź reached its peak population in 1989. It was 851 690 residents. In 2000, this number fell below 800 thousand, but until July 2007 we still had a larger population than Kraków.

Currently Łódź's population numbers nearly 700 thousand people. This refers to people registered as residents in the city; these figures do not include, for example, most students who flow into the city year after year from other towns and often decide to stay. The University of Łódź alone has approximately 40 thousand students, while the Łódź University of Technology has nearly 17 thousand.

According to registration data, of nearly 700 thousand residents, only 457 thousand were born in Łódź. The rest are people who over the years came to the city from other towns in Poland and around the world.