How far is Rockford, IL from Johnston City, IL?
The driving distance from Rockford, IL to Johnston City, IL is about 336.7 miles (541.9 km), with a travel time of about 06h 32m by car.
- The straight-line flight distance is about 307.6 miles (495.1 km).
- For a round trip, plan for roughly 13h 04m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 6:00 AM to 7:30 AM CDT.
Reverse, save, or send this route
This drive is better planned with a longer stop or an overnight stay. Copy the route link, send it to another device, or print a clean version before you head out.
This drive is better planned with a longer stop or an overnight stay.
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 06h 32m.
Starting early still helps, but most travelers will want a longer stop or an overnight stay on a route this long.
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 Illinois, USA
Route Weather Snapshot
Check the forecast at both ends before you head out.
Partly Sunny
Mostly Sunny
Driving Route Map
The map below follows the saved road route between Rockford and Johnston City.
Turn-by-Turn Driving Directions
Step-by-step road directions between Rockford and Johnston City.
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1
Start on West State Street
546 ft · 23 sec · West State Street
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2
Turn left onto South Church Street
1519 ft · 37 sec · South Church Street
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3
Turn left onto Cedar Street
84 m · 5 sec · Cedar Street
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4
Turn right onto South Main Street
3.6 mi · 6 min · South Main Street
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5
Take the ramp left
1707 ft · 44 sec
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6
Merge slight left onto U.S. Grant Memorial Highway
4.3 mi · 5 min · U.S. Grant Memorial Highway
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7
Take the exit slight right
1.2 km · 2 min
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8
Merge slight right
118.2 mi · 2 hr 7 min
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9
Keep slight right to continue on I 55 South, US 51 South: Peoria, Champaign, Saint Louis, Decatur
7.6 mi · 8 min
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10
Keep slight left to continue on I 74 East, US 51 South, US 55 Business North: Indianapolis, Decatur
2.1 mi · 2 min
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11
Take the exit slight right toward US 51 South, US 51 Business North: Decatur, Bloomington
1616 ft · 40 sec
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12
Continue on North 1450 East Road
14.7 mi · 18 min · North 1450 East Road
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13
Continue on North Walnut Street
23.2 mi · 30 min · North Walnut Street
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14
Turn straight
9.9 mi · 15 min
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15
Take the ramp straight toward South Business Route 51
19.6 mi · 24 min · South Business Route 51
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16
Continue on North 2600 East Rd
7.9 mi · 9 min · North 2600 East Rd
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17
Turn right onto North 2600 East Road
1.6 km · 2 min · North 2600 East Road
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18
Continue on Jackson Street
2668 ft · 2 min · Jackson Street
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19
Turn left onto Cedar Street
142 m · 8 sec · Cedar Street
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20
Turn right onto East 1st Street
2150 ft · 1 min · East 1st Street
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21
Turn left onto South Poplar Street
2138 ft · 30 sec · South Poplar Street
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22
Turn straight onto Fair Avenue
3070 ft · 2 min · Fair Avenue
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23
Continue on County Road 2400 E
2 mi · 3 min · County Road 2400 E
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24
Continue on 300 East Road
15.1 mi · 17 min · 300 East Road
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25
Continue on County Road 875 East
11.1 mi · 13 min · County Road 875 East
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26
Continue on North Kennedy Boulevard
1.5 mi · 2 min · North Kennedy Boulevard
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27
Turn left onto West Gallatin Street
2405 ft · 34 sec · West Gallatin Street
-
28
Turn right
554 ft · 7 sec
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29
Continue on United States Highway 51
13.4 mi · 15 min · United States Highway 51
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30
Continue on 250E
10.4 mi · 12 min · 250E
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31
Turn left
7.6 mi · 9 min
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32
Take the exit left
1847 ft · 45 sec
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33
Merge slight left
24.5 mi · 27 min
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34
Keep slight right to continue on Ken Gray Expressway
32.7 mi · 35 min · Ken Gray Expressway
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35
Take the exit slight right toward Johnston City, Herrin
1506 ft · 42 sec
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36
Turn left onto Herrin Road
1115 ft · 19 sec · Herrin Road
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37
Continue on West Broadway Boulevard
1.6 km · 2 min · West Broadway Boulevard
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38
Turn left onto Washington Avenue
808 ft · 41 sec · Washington Avenue
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39
At the end of the road, turn left onto East 9th Street
15 m · 4 sec · East 9th Street
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40
Turn right onto Washington Avenue
620 ft · 27 sec · Washington Avenue
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41
Arrive at your destination
0 m · 1 sec · Washington Avenue
Car Route Details
A richer read on the saved driving route between Rockford and Johnston City.
Long-distance drive
This route is long enough that fuel, rest stops, weather, and timing matter more than any single maneuver.
U.S. Grant Memorial Highway
Merge slight right
118 mi · 02h 07m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
Better with a longer stop
This route is long enough that most travelers will be better off planning an overnight stay or a more deliberate stop window.
Partly Sunny leaving Rockford and Mostly Sunny near Johnston City.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Rockford to Johnston City?
The road trip is about 336.7 miles (541.9 km) and usually takes 06h 32m in normal driving conditions.
Is this a same-day trip or an overnight route?
This route is long enough that most travelers will be better off planning an overnight stay or a more deliberate stop window.
What is the halfway point on this route?
Maroa is a useful midpoint, sitting about 168.5 miles from Rockford and 168.2 miles from Johnston City.
How much longer is the road route than the straight-line distance?
The direct path is about 307.6 miles (495.1 km), while the road route adds roughly 29.1 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 6:00 AM to 7:30 AM CDT. Starting early still helps, but most travelers will want a longer stop or an overnight stay on a route this long.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $44.80 one way or $89.60 round trip. Estimated CO2 is about 105.6 kg one way.
What should you check before leaving?
Before you leave, expect Partly Sunny around Rockford and Mostly Sunny near Johnston City.
Stop Ideas Near Maroa
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
Clinton City Hall
Warrensburg Village Hall
City of Decatur
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Maroa.
Lincoln
Uptown Station
Illinois Terminal
Springfield station
Flight Path Map
This map shows the direct air route between Rockford and Johnston City. Straight-line distance: 307.63 mi (495.08 km).
#1 Rockford
The second most populous city in Illinois.
| Population | 144,835 |
| Coordinates | 42.2711300, -89.0940000 |
| Altitude | 218 |
| Country | United States |
#2 Johnston City
City in Illinois, United States
| Population | 3,389 |
| Coordinates | 37.8206100, -88.9275700 |
| Altitude | 130 |
| Country | United States |
End: Johnston City (-88.92757, 37.82061)
Estimated Travel Time
Distance: 542 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 11h 13m |
| 40 mph (64.37 km/h) | 08h 25m |
| 50 mph (80.47 km/h) | 06h 44m |
| 60 mph (96.56 km/h) | 05h 36m |
| 70 mph (112.65 km/h) | 04h 48m |
| 80 mph (129 km/h) | 04h 12m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $44.80 | $89.60 |
| Mid-grade | $4.25 | $50.53 | $101.05 |
| Premium | $4.65 | $55.29 | $110.58 |
| Diesel | $5.30 | $63.01 | $126.02 |
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 Illinois · Jun 02, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.