How far is O'Fallon, MO from Gray Summit, MO?
The driving distance from O'Fallon, MO to Gray Summit, MO is about 32.7 miles (52.7 km), with a travel time of about 00h 51m by car.
- The straight-line flight distance is about 23.1 miles (37.1 km).
- For a round trip, plan for roughly 01h 43m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 8:00 AM to 10:00 AM CDT.
Reverse, save, or send this route
This route works well as a day trip with time at the destination. Copy the route link, send it to another device, or print a clean version before you head out.
This route works well as a day trip with time at the destination.
Flight Distance
Driving Distance
Gas Cost Calculator
Leave and Arrive Planner
Pick a departure time to see your estimated arrival and same-day return window.
Drive time stays fixed at 00h 51m.
A morning start gives you useful time at the destination and keeps the return out of the late evening.
You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
City in New Jersey
Route Weather Snapshot
Check the forecast at both ends before you head out.
Partly Sunny then Slight Chance Showers And Thunderstorms
Partly Sunny then Chance Showers And Thunderstorms
Driving Route Map
The map below follows the saved road route between O'Fallon and Gray Summit.
Turn-by-Turn Driving Directions
Step-by-step road directions between O'Fallon and Gray Summit.
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1
Start on the route
8 m · 7 sec
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2
Turn left onto South Main Street
2865 ft · 1 min · South Main Street
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3
Continue straight
3.1 mi · 6 min
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4
Continue straight
3.4 mi · 5 min
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5
Take the ramp slight right toward I 64 East, US 40 East, US 61 South
1523 ft · 22 sec
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6
Merge slight left onto Avenue of the Saints
3.7 mi · 5 min · Avenue of the Saints
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7
Take the exit slight right toward Chesterfield Airport Road
2700 ft · 58 sec
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8
Continue on Chesterfield Airport Road
110 m · 7 sec · Chesterfield Airport Road
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9
Turn right onto Olive Street Road
64 m · 5 sec
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10
Turn right onto Olive Street Road
1.5 km · 2 min · Olive Street Road
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11
Continue on North Eatherton Road
2.4 mi · 5 min · North Eatherton Road
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12
Enter the roundabout and take exit 2 toward the route
21 m · 1 sec
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13
Exit the roundabout
4.3 mi · 7 min
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14
Enter the roundabout and take exit 2 toward the route
29 m · 2 sec
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15
Exit the roundabout
2098 ft · 45 sec
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16
Enter the roundabout and take exit 2 toward MO 100 West: Gray Summit
23 m · 2 sec
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17
Exit the roundabout onto MO 100 West: Gray Summit
1202 ft · 33 sec
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18
Merge slight left
12.8 mi · 18 min
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19
Arrive at your destination
0 m · 1 sec
Car Route Details
A richer read on the saved driving route between O'Fallon and Gray Summit.
Turn-heavy local drive
The route has frequent decision points for its length, so lane choice and turn timing will matter more than cruising speed.
MO 100 West
Merge slight left
12.8 mi · 00h 18m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A comfortable day-trip route
This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.
Partly Sunny then Slight Chance Showers And Thunderstorms leaving O'Fallon and Partly Sunny then Chance Showers And Thunderstorms near Gray Summit.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from O'Fallon to Gray Summit?
The road trip is about 32.7 miles (52.7 km) and usually takes 00h 51m in normal driving conditions.
Is this a same-day trip or an overnight route?
This route works well as a day trip. You can leave in the morning, spend meaningful time at the destination, and still return the same day.
What is the halfway point on this route?
Wildwood is a useful midpoint, sitting about 16.4 miles from O'Fallon and 16.4 miles from Gray Summit.
How much longer is the road route than the straight-line distance?
The direct path is about 23.1 miles (37.1 km), while the road route adds roughly 9.6 extra miles because roads do not follow the straight air line.
When is the best time to leave for this route?
A good departure window is usually 8:00 AM to 10:00 AM CDT. If you want a more comfortable same-day return, try to leave by 4:46 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $4.37 one way or $8.75 round trip. Estimated CO2 is about 10.3 kg one way.
What should you check before leaving?
Before you leave, expect Partly Sunny then Slight Chance Showers And Thunderstorms around O'Fallon and Partly Sunny then Chance Showers And Thunderstorms near Gray Summit.
Stop Ideas Near Wildwood
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
City Hall Park
City of O'Fallon
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Wildwood.
Kirkwood
Washington
Gateway Transportation Center
Alton
Flight Path Map
This map shows the direct air route between O'Fallon and Gray Summit. Straight-line distance: 23.05 mi (37.09 km).
#1 O'Fallon
The most populous city in St.
| Population | 89,769 |
| Coordinates | 38.8106100, -90.6998500 |
| Altitude | 165 |
| Country | United States |
#2 Gray Summit
Census designated place
| Population | 2,701 |
| Coordinates | 38.4897800, -90.8168000 |
| Altitude | 203 |
| Country | United States |
End: Gray Summit (-90.8168, 38.48978)
Estimated Travel Time
Distance: 53 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 01h 05m |
| 40 mph (64.37 km/h) | 00h 49m |
| 50 mph (80.47 km/h) | 00h 39m |
| 60 mph (96.56 km/h) | 00h 32m |
| 70 mph (112.65 km/h) | 00h 28m |
| 80 mph (129 km/h) | 00h 24m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $4.37 | $8.75 |
| Mid-grade | $4.25 | $4.93 | $9.87 |
| Premium | $4.65 | $5.40 | $10.80 |
| Diesel | $5.30 | $6.15 | $12.31 |
Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.
Prices in Missouri · May 23, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.