Chicago Marathon
Chicago, United States of America · Sunday 11 October 2026
The Chicago Marathon is a large annual road race held in the city of Chicago, Illinois, typically occurring on the first or second Sunday of October. The event hosts approximately 40,000 runners, making it one of the largest marathons globally. The course forms a loop through downtown Chicago and many neighborhoods, covering a standard marathon distance of 42.195 kilometers (26.22 miles).
Difficulty Calculator
h
:m
:s
Adjusted Time
3:55:36
Time difference: -4.4 minutes compared to a flat, road, temperate course.
Course Details
Elevation Gain74m
Elevation High187m
Elevation Low177m
Weather Forecast
High18°C
Low11°C
Chance of Rain0%
How hard is Chicago Marathon?
Moderateharder than 19% of marathons
Flattest / easiestHardest
On our difficulty model, Chicago Marathon plays about 1 minute slower than an average road marathon for a 3:30 runner. It ranks #931 hardest of 1151 marathons we analyse, and #450 of 576 in United States of America. Use the calculator above to see the exact adjusted time for your own goal pace.
What will you run at Chicago Marathon?
Estimated finish times on this course versus the same effort on an average road marathon, based on its elevation, surface, and expected race-day temperature.
| Average-course time | On Chicago Marathon | Difference |
|---|---|---|
| 3:00:00 | 2:55:42 | −04:18 |
| 3:30:00 | 3:25:40 | −04:20 |
| 4:00:00 | 3:55:36 | −04:24 |
| 4:30:00 | 4:25:31 | −04:29 |
| 5:00:00 | 4:55:25 | −04:35 |
| 5:30:00 | 5:25:17 | −04:43 |
| 6:00:00 | 5:55:08 | −04:52 |
Use the calculator above for your exact goal time. Want a prediction from your own training? Try the marathon time predictor.
Chicago Marathon 2026 Course Analysis
Chicago Marathon is a full marathon held in Chicago, United States of America. It is scheduled for Sunday 11 October 2026. The course is run on road surface with 74m of total climbing, with its high point near 187m above sea level. For registration and full race details, visit the official Chicago Marathon website.
Elevation Profile
This is a very flat course, with only 74m of total climbing and little change in altitude throughout. Flat profiles let you hold an even pace from start to finish, which makes this a fast, PB-friendly race.
Expected Race Day Weather
Based on historical weather data for October, the expected race day conditions are as follows. Near-ideal running temperatures are expected, ranging from 11°C to 18°C. This temperature range is widely considered optimal for marathon performance, allowing efficient heat dissipation without cold-related issues. There is a low chance of rain (0%), so dry conditions are likely.
Surface Type: Road
Chicago Marathon is run on road surfaces, which provide the fastest and most predictable conditions for racing. Road courses allow for consistent pacing and are typically the best choice for a personal best.
Looking for an easier marathon or a tougher challenge? You can also compare Chicago Marathon against other marathons to find the right race for your goals.
Marathons of similar difficulty
If Chicago Marathon fits your goal, these courses play out about the same on our difficulty model.
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