- Weather
- 46°Ftypical startModelled estimate
- Field size
- ~400 runners
- Course
- Flat
- Elevation
- 200 ft gain · 0 ft net
Event: Athens Marathon
PR9Weather9Experience6
Early October · Midwest · Loop
Chicago Marathon
Chicago, IL · Monday, October 12, 2026
Flat, fast, and it stays that way on purpose: a single loop through downtown and the neighborhoods with almost no elevation change to fight, which is exactly why it has produced multiple world records. The course threads through areas like Chinatown, Pilsen, and Boystown before returning to a Grant Park finish near the Lake Michigan shoreline.
World Marathon Major; world-record fast
- Best for PR
- Boston Qualifier
- First Marathon
- Bucket List
- Big Race Experience
Opens the race organizer's website
Typical start
47°
Cooler than 58% of U.S. marathons
Modeled historical conditions
Elevation gain
250ft
Flatter than 48% of races
Estimated total climb
Field size
48K
Larger than 99% of races
Estimated field
PR potential
8.9/10
Ahead of 51% of races
Almanac model
Percentiles compare this race against all 224 U.S. marathons in the Almanac.
Course profile
250 ft gain
Flat course, loop.
0510152026.2
Race-day weather
Modeled from location, month and coastal proximity, not verified race history.
6 AM
39°
Start
47°
Midday
58°
ExcellentGoodWarmHeat risk
Typical start sits at 47°F, excellent marathon conditions.
Typical dew point 40°F, 22% chance of precipitation, wind around 10 mph. All modeled.
The bottom line
Few marathons combine this much speed with this much spectacle.
Chicago Marathon is a strong choice for a PR attempt, and Chicago offers very little meaningful elevation. The tradeoff is scale: race morning is complicated and you are sharing the course with a very large field.
Why runners choose this race
A loop course around Chicago, IL, with very little meaningful elevation change.
The case for it
- PR attempts
- Boston qualification
- First-time marathoners
- Big-race atmosphere
The tradeoffs
- You dislike crowded starts and corrals
Course and logistics
- Course type
- Loop
- Surface
- Road
- Profile
- Flat
- Total gain
- 250 ft(estimated)
- Field size
- ~45,000-50,000 runners(estimated)
- Crowd support
- Wall-to-wall crowds
- Entry
- Data coming soon
- Start / finish
- Start and finish in the same area
Race details
- Typical timing
- Early October
- Next confirmed date
- Monday, October 12, 2026
- Region
- Midwest
- Editorial tier
- Featured
- Data last reviewed
- 2026-08-26
- Best for PR
- Boston Qualifier
- First Marathon
- Bucket List
- Big Race Experience
- World Marathon Major
- Loop course
- Flat course
- Destination race
Similar races
Races with a comparable profile.
- Weather
- 44°Ftypical startModelled estimate
- Field size
- ~1,800 runners
- Course
- Flat
- Elevation
- 180 ft gain · 0 ft net
Event: Carmel Marathon
PR9Weather9Experience7
- Weather
- 52°Ftypical startModelled estimate
- Field size
- ~300 runners
- Course
- Flat
- Elevation
- 150 ft gain · 0 ft net
Event listed as: Marathon
PR9Weather9Experience6