How far is San Antonio, TX from Karnes City, TX?
The driving distance from San Antonio, TX to Karnes City, TX is about 53.9 miles (86.7 km), with a travel time of about 01h 03m by car.
- The straight-line flight distance is about 51.6 miles (83.1 km).
- For a round trip, plan for roughly 02h 07m 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 01h 03m.
A morning start gives you useful time at the destination and keeps the return out of the late evening.
This departure sits inside the recommended comfort window for the route.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
City in Texas, United States
Route Weather Snapshot
Check the forecast at both ends before you head out.
Mostly Cloudy
Partly Sunny
Driving Route Map
The map below follows the saved road route between San Antonio and Karnes City.
Turn-by-Turn Driving Directions
Step-by-step road directions between San Antonio and Karnes City.
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1
Start on Dolorosa Street
44 m · 5 sec · Dolorosa Street
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2
Continue on West Market Street
1893 ft · 42 sec · West Market Street
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3
Continue on East Market Street
2143 ft · 41 sec · East Market Street
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4
Turn right onto Tower of the Americas Way
957 ft · 21 sec · Tower of the Americas Way
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5
Take the ramp slight left toward I 37 South, US 281 South
1374 ft · 34 sec
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6
Merge slight left onto William J Bordelon Freeway
1.4 mi · 2 min · William J Bordelon Freeway
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7
Continue on Lucian Adams Freeway
7.4 mi · 8 min · Lucian Adams Freeway
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8
Take the exit slight right toward US 181 South: Floresville
43.2 mi · 50 min
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9
Turn left onto West Calvert Avenue
3177 ft · 1 min · West Calvert Avenue
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10
Arrive at your destination
0 m · 1 sec · East Calvert Avenue
Car Route Details
A richer read on the saved driving route between San Antonio and Karnes City.
Highway-focused drive
Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.
US 181 South
Take the exit slight right toward US 181 South: Floresville
43.2 mi · 00h 50m
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.
Mostly Cloudy leaving San Antonio and Partly Sunny near Karnes City.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from San Antonio to Karnes City?
The road trip is about 53.9 miles (86.7 km) and usually takes 01h 03m 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?
Floresville is a useful midpoint, sitting about 27 miles from San Antonio and 26.9 miles from Karnes City.
How much longer is the road route than the straight-line distance?
The direct path is about 51.6 miles (83.1 km), while the road route adds roughly 2.3 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 4:22 PM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $7.18 one way or $14.36 round trip. Estimated CO2 is about 16.9 kg one way.
What should you check before leaving?
Before you leave, expect Mostly Cloudy around San Antonio and Partly Sunny near Karnes City.
Stop Ideas Near Floresville
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Floresville.
San Antonio Station
San Marcos Station
Flight Path Map
This map shows the direct air route between San Antonio and Karnes City. Straight-line distance: 51.64 mi (83.11 km).
#1 San Antonio
The seventh most populous city in the United States and the center of the San Antonio metropolitan area.
| Population | 1,567,118 |
| Coordinates | 29.4241200, -98.4936300 |
| Altitude | 198 |
| Country | United States |
#2 Karnes City
City in Karnes County, Texas, United States
| Population | 3,383 |
| Coordinates | 28.8849800, -97.9008400 |
| Altitude | 131 |
| Country | United States |
End: Karnes City (-97.90084, 28.88498)
Estimated Travel Time
Distance: 87 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 01h 47m |
| 40 mph (64.37 km/h) | 01h 20m |
| 50 mph (80.47 km/h) | 01h 04m |
| 60 mph (96.56 km/h) | 00h 53m |
| 70 mph (112.65 km/h) | 00h 46m |
| 80 mph (129 km/h) | 00h 40m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.78 | $7.18 | $14.36 |
| Mid-grade | $4.25 | $8.08 | $16.16 |
| Premium | $4.59 | $8.72 | $17.45 |
| Diesel | $3.99 | $7.59 | $15.17 |
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 Texas · Apr 17, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.