Chicago Marathon
Chicago, USA · Second Sunday of October
Pancake-flat loop through 29 neighborhoods with enormous crowd support. The only 'climb' is a highway overpass at kilometre 41. Tall buildings can confuse GPS early — run by feel and the split clocks.
Course
Elevation gain
74 m
Net elevation
+1 m
Finishers
~52,000
Month
October
Second Sunday of October
Race-day weather
Median start temp
10°C
Historical range
2–24°C
Hot-year risk
Moderate
October in Chicago is a coin flip: crisp 5°C mornings most years, but 2007-style heat is possible.
Getting in
Qualifier or lottery. Guaranteed entry with time qualifiers; otherwise lottery in the fall a year ahead. Official site ↗
Pacing plans for Chicago Marathon
Course-adjusted splits for every common goal — not flat even splits, but pacing that matches where this course is fast and where it bites.
Frequently asked questions
Is the Chicago Marathon a fast course?
Yes — it is one of the fastest marathon courses in the world. The course has 74 m of total elevation gain. We rate it 9/10 for PR potential.
What is the weather usually like at the Chicago Marathon?
The median start-line temperature is around 10°C, with a historical range of roughly 2–24°C. October in Chicago is a coin flip: crisp 5°C mornings most years, but 2007-style heat is possible.
How do you get into the Chicago Marathon?
Qualifier or lottery. Guaranteed entry with time qualifiers; otherwise lottery in the fall a year ahead.
Is the Chicago Marathon a Boston qualifier?
Yes — the Chicago Marathon is a certified course accepted by the B.A.A. for Boston qualifying times.