How far is Gillette, WY from Thermopolis, WY?

The driving distance from Gillette, WY to Thermopolis, WY is about 194.5 miles (313 km), with a travel time of about 04h 06m by car.

  • The straight-line flight distance is about 141.9 miles (228.4 km).
  • For a round trip, plan for roughly 08h 13m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 6:00 AM to 8:00 AM MDT.
Trip Tools

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.

Reverse Route
Quick Snapshot
Road
194.5 mi
04h 06m
Flight
141.92 mi
228.4 km direct

This drive is better planned with a longer stop or an overnight stay.

Learn Distance

Choose another destination from Gillette.

Flight Distance

Direct air line
141.92 mi
Kilometers
228.4 km
Flight Time
00h 17m

Driving Distance

Road route
194.5 mi
Kilometers
313.02 km
Drive Time
04h 06m

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 04h 06m.

Arrival Snapshot
Arrive in Thermopolis
Thu, Apr 23, 3:17 AM MDT
Return by in Gillette
Thu, Apr 23, 7:24 AM MDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Gillette
2026-04-22T23:11
Arrive Thermopolis
Thu, Apr 23, 3:17 AM MDT
Route Timing
04h 06m
One way by road
Best Departure Window
6:00 AM to 8:00 AM MDT
Leave early for more breathing room
Arrive between
10:07 AM to 12:07 PM MDT

An early departure helps you fit a real stop into the day without turning the return into a late-night drive.

Leave by
8:46 AM MDT
Keeps a same-day return open with about 04h 00m at the destination.
Back in Gillette
9:00 PM MDT
Early departure recommended

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.

Mid-route stop
Buffalo
WY

City in and county seat of Johnson County, Wyoming, United States

From Gillette
97.1 mi
02h 03m
To Thermopolis
97.4 mi
02h 03m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
76°F
Wednesday

Mostly Sunny

Starts
Wed, Apr 22 6:00 AM MDT
Wind
14 to 29 mph SW
Destination
72°F
Wednesday

Sunny

Starts
Wed, Apr 22 6:00 AM MDT
Wind
10 to 31 mph SSW

Driving Route Map

The map below follows the saved road route between Gillette and Thermopolis.

Turn-by-Turn Driving Directions

Step-by-step road directions between Gillette and Thermopolis.

  1. 1

    Start on East 4th Street

    2116 ft · 1 min · East 4th Street

  2. 2

    Turn right onto South Douglas Highway

    1.2 km · 2 min · South Douglas Highway

  3. 3

    Take the ramp right

    67.4 mi · 1 hr 5 min

  4. 4

    Take the exit slight right toward US 16, I 90 Business: Buffalo Ucross

    1112 ft · 34 sec

  5. 5

    Turn left onto US Highway 16 East

    1.6 mi · 2 min · US Highway 16 East

  6. 6

    Continue on East Hart Street

    1 km · 1 min · East Hart Street

  7. 7

    At the end of the road, turn left onto North Main Street

    2195 ft · 41 sec · North Main Street

  8. 8

    Turn right onto Fort Street

    96.9 mi · 2 hr 22 min · Fort Street

  9. 9

    Continue straight

    25.9 mi · 32 min

  10. 10

    Continue on North 6th Street

    1608 ft · 49 sec · North 6th Street

  11. 11

    Arrive at your destination

    0 m · 1 sec · South 6th Street

Car Route Details

A richer read on the saved driving route between Gillette and Thermopolis.

OSRM road route
Drive Character

Straightforward drive

The saved road route has a manageable number of maneuvers and should be easy to follow with normal attention to signs.

Directions
11 steps
4 turns on the saved route
Ramps & Exits
2
0 merges, 2 ramps or exits
Navigation Density
5.7 / 100 mi
Decision points by distance
Main Roads
Fort Street
123 mi · 63%
South Douglas Highway
68.2 mi · 35%
US Highway 16 East
1.56 mi · 1%
East Hart Street
0.64 mi
North Main Street
0.42 mi
East 4th Street
0.4 mi
Longest Stretch

Fort Street

Turn right onto Fort Street

96.9 mi · 02h 22m

Route Summary

A quick read on whether this route feels easy, ambitious, or worth planning around.

Trip Read

A longer out-and-back drive

This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.

Drive Time
04h 06m
Long day trip
Same-Day Return
08h 14m
Round-trip wheel time
Road vs Air
+52.6 mi
141.9 mi direct line
Halfway Stop
Buffalo
02h 03m from Gillette
Leave By
8:46 AM MDT
Early departure recommended
Weather Watch

Mostly Sunny leaving Gillette and Sunny near Thermopolis.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from Gillette to Thermopolis?

The road trip is about 194.5 miles (313 km) and usually takes 04h 06m in normal driving conditions.

Is this a same-day trip or an overnight route?

This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.

What is the halfway point on this route?

Buffalo is a useful midpoint, sitting about 97.1 miles from Gillette and 97.4 miles from Thermopolis.

How much longer is the road route than the straight-line distance?

The direct path is about 141.9 miles (228.4 km), while the road route adds roughly 52.6 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 6:00 AM to 8:00 AM MDT. If you want a more comfortable same-day return, try to leave by 8:46 AM MDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $26.71 one way or $53.41 round trip. Estimated CO2 is about 61 kg one way.

What should you check before leaving?

Before you leave, expect Mostly Sunny around Gillette and Sunny near Thermopolis.

Flight Path Map

This map shows the direct air route between Gillette and Thermopolis. Straight-line distance: 141.92 mi (228.4 km).

Gillette

#1 Gillette

City in Campbell County, Wyoming, United States

Population32,220
Coordinates44.2910900, -105.5022200
Altitude1388
CountryUnited States
Thermopolis

#2 Thermopolis

Town of the United States

Population2,770
Coordinates43.6460700, -108.2120400
Altitude1320
CountryUnited States
Start: Gillette (-105.50222, 44.29109)
End: Thermopolis (-108.21204, 43.64607)

Estimated Travel Time

Distance: 313 km by road

SpeedTime
30 mph (48.3 km/h)06h 28m
40 mph (64.37 km/h)04h 51m
50 mph (80.47 km/h)03h 53m
60 mph (96.56 km/h)03h 14m
70 mph (112.65 km/h)02h 46m
80 mph (129 km/h)02h 25m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
6.86 gal
25.98 L · about $26.71
Round trip
$53.41
13.72 gal · 51.96 L
Estimated CO2
61 kg one way
Round trip: 121.9 kg / 269 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $3.89 $26.71 $53.41
Mid-grade $4.23 $29.02 $58.05
Premium $4.55 $31.21 $62.41
Diesel $5.41 $37.13 $74.25

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 Wyoming · Apr 23, 2026

There is no time difference between Gillette and Thermopolis. The current time is 23:11:14.

Distance to Other Cities

Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.

How did we calculate? Place names are translated into coordinates. The Haversine formula calculates straight-line distance; driving distance uses road network data.