On Sunday, October 8, tens of thousands of runners hit the streets of the Windy City to compete in the 2023 Chicago Marathon.
You may have heard about it. A young runner from Kenya, Kelvin Kiptum, set a new world record. So it’s kind of a big deal.
But how does this year’s Chicago Marathon compare to past races? Was this just a great day for Kelvin Kiptum — or was it a great day for everyone who ran?
Let’s take a look at the data and find out.

Photo by Miguel A Amutio on Unsplash
Field Size and Composition
Chicago is the second-largest marathon in the United States, and it is always big.