How far is Key Largo, FL from St. Petersburg, FL?

The driving distance from Key Largo, FL to St. Petersburg, FL is about 308.4 miles (496.4 km), with a travel time of about 04h 50m by car.

  • The straight-line flight distance is about 231.2 miles (372.1 km).
  • For a round trip, plan for roughly 09h 40m of driving time before adding stops, traffic, or weather delays.
  • A comfortable departure window is usually 6:00 AM to 8:00 AM EDT.
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
308.45 mi
04h 50m
Flight
231.22 mi
372.12 km direct

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

Learn Distance

Choose another destination from Key Largo.

Flight Distance

Direct air line
231.22 mi
Kilometers
372.12 km
Flight Time
00h 27m

Driving Distance

Road route
308.45 mi
Kilometers
496.4 km
Drive Time
04h 50m

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 50m.

Arrival Snapshot
Arrive in St. Petersburg
Thu, May 7, 2:46 AM EDT
Return by in Key Largo
Thu, May 7, 7:36 AM EDT
Useful when you're deciding between a quick errand, a day trip, or a longer stop.
Leave Key Largo
2026-05-06T21:56
Arrive St. Petersburg
Thu, May 7, 2:46 AM EDT
Route Timing
04h 50m
One way by road
Best Departure Window
6:00 AM to 8:00 AM EDT
Leave early for more breathing room
Arrive between
10:50 AM to 12:50 PM EDT

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

Leave by
7:20 AM EDT
Keeps a same-day return open with about 04h 00m at the destination.
Back in Key Largo
9:00 PM EDT
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
Golden Gate
FL

Census designated place

From Key Largo
154.2 mi
02h 25m
To St. Petersburg
154.2 mi
02h 25m

Route Weather Snapshot

Check the forecast at both ends before you head out.

Origin
84°F
Wednesday

Slight Chance Rain Showers

Starts
Wed, May 6 6:00 AM EDT
Wind
5 mph SE
Destination
73°F
Tonight

Partly Cloudy

Starts
Wed, May 6 7:00 PM EDT
Wind
2 to 8 mph WSW

Driving Route Map

The map below follows the saved road route between Key Largo and St. Petersburg.

Turn-by-Turn Driving Directions

Step-by-step road directions between Key Largo and St. Petersburg.

  1. 1

    Start on Harbor Drive

    94 m · 16 sec · Harbor Drive

  2. 2

    Turn right onto Overseas Highway

    9.3 mi · 16 min · Overseas Highway

  3. 3

    Continue on Dixie Highway

    19.4 mi · 27 min · Dixie Highway

  4. 4

    Take the exit slight right toward Miami, Orlando, Florida's Turnpike North

    1785 ft · 38 sec

  5. 5

    Continue on Homestead Extension of Florida's Turnpike

    13.2 mi · 16 min · Homestead Extension of Florida's Turnpike

  6. 6

    Keep slight right to continue on Homestead Extension of Florida's Turnpike

    3.6 mi · 5 min · Homestead Extension of Florida's Turnpike

  7. 7

    Keep slight left to continue on Homestead Extension of Florida's Turnpike

    2.5 mi · 3 min · Homestead Extension of Florida's Turnpike

  8. 8

    Keep slight right to continue on Homestead Extension of Florida's Turnpike

    15.5 mi · 18 min · Homestead Extension of Florida's Turnpike

  9. 9

    Take the exit slight right toward US 27: Okeechobee Road

    1140 ft · 28 sec

  10. 10

    Keep slight right to continue on US 27: Okeechobee Road

    633 ft · 16 sec

  11. 11

    Merge slight left onto Okeechobee Road

    17.6 mi · 23 min · Okeechobee Road

  12. 12

    Take the exit slight right toward I 75: Miami, Fort Lauderdale, Naples

    1360 ft · 33 sec

  13. 13

    Keep slight left to continue on I 75 North: Naples

    1.3 km · 2 min

  14. 14

    Merge slight left onto Alligator Alley

    203.5 mi · 3 hr 38 min · Alligator Alley

  15. 15

    Take the exit slight right toward I 275 North: Saint Petersburg

    5.7 mi · 8 min

  16. 16

    Keep slight left

    1610 ft · 20 sec

  17. 17

    Merge slight right onto Sunshine Skyway Bridge

    14.3 mi · 17 min · Sunshine Skyway Bridge

  18. 18

    Take the exit slight left toward 31st Street South

    1604 ft · 39 sec

  19. 19

    Keep slight left to continue on Winery, Treasure Island, Tropicana Field

    49 m · 10 sec

  20. 20

    Turn left onto 31st Street South

    2167 ft · 58 sec · 31st Street South

  21. 21

    Turn left onto 5th Avenue South

    1303 ft · 40 sec · 5th Avenue South

  22. 22

    Turn right onto 34th Street South

    1589 ft · 41 sec · 34th Street South

  23. 23

    Arrive at your destination

    0 m · 1 sec · 34th Street South

Car Route Details

A richer read on the saved driving route between Key Largo and St. Petersburg.

OSRM road route
Drive Character

Long-distance drive

This route is long enough that fuel, rest stops, weather, and timing matter more than any single maneuver.

Directions
23 steps
9 turns on the saved route
Ramps & Exits
8
3 merges, 5 ramps or exits
Navigation Density
7.5 / 100 mi
Decision points by distance
Main Roads
Alligator Alley
203 mi · 66%
Homestead Extension of Florida's Turnpike
34.8 mi · 11%
Dixie Highway
19.4 mi · 6%
Okeechobee Road
17.6 mi · 6%
Sunshine Skyway Bridge
14.3 mi · 5%
Overseas Highway
9.29 mi · 3%
Longest Stretch

Alligator Alley

Merge slight left onto Alligator Alley

203 mi · 03h 38m

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 50m
Long day trip
Same-Day Return
09h 40m
Round-trip wheel time
Road vs Air
+77.2 mi
231.2 mi direct line
Halfway Stop
Golden Gate
02h 25m from Key Largo
Leave By
7:20 AM EDT
Early departure recommended
Weather Watch

Slight Chance Rain Showers leaving Key Largo and Partly Cloudy near St. Petersburg.

Trip Questions

Direct answers travelers usually want before committing to the drive.

How long does it take to drive from Key Largo to St. Petersburg?

The road trip is about 308.4 miles (496.4 km) and usually takes 04h 50m 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?

Golden Gate is a useful midpoint, sitting about 154.2 miles from Key Largo and 154.2 miles from St. Petersburg.

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

The direct path is about 231.2 miles (372.1 km), while the road route adds roughly 77.2 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 EDT. If you want a more comfortable same-day return, try to leave by 7:20 AM EDT.

How much will gas cost for this route?

Using about 28.3 MPG, regular gas is estimated at $45.13 one way or $90.26 round trip. Estimated CO2 is about 96.7 kg one way.

What should you check before leaving?

Before you leave, expect Slight Chance Rain Showers around Key Largo and Partly Cloudy near St. Petersburg.

Stop Ideas Near Golden Gate

Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.

Mid-route Guidance
Local place coverage is thin around Golden Gate, so nearby transit and meeting points are shown instead.
Reviewed stop coverage is still thin around this midpoint, so practical transit waypoints are shown on the right.

Transit and Meeting Points

Useful pickup, handoff, or rendezvous points close to Golden Gate.

BUS

Fort Myers, Florida

58 mi away
6050 Plaza Drive
BUS

Port Charlotte, Florida

98 mi away
909 King Highway

Flight Path Map

This map shows the direct air route between Key Largo and St. Petersburg. Straight-line distance: 231.22 mi (372.12 km).

Key Largo

#1 Key Largo

Census designated place in Florida, United States

Population10,433
Coordinates25.0865200, -80.4472800
Altitude2
CountryUnited States
St. Petersburg

#2 St. Petersburg

The second most populous city in Florida.

Population253,693
Coordinates27.7708600, -82.6792700
Altitude13
CountryUnited States
Start: Harbor Drive (-80.44767, 25.086521)
End: US 19 (-82.679372, 27.77086)

Estimated Travel Time

Distance: 496 km by road

SpeedTime
30 mph (48.3 km/h)10h 16m
40 mph (64.37 km/h)07h 42m
50 mph (80.47 km/h)06h 10m
60 mph (96.56 km/h)05h 08m
70 mph (112.65 km/h)04h 24m
80 mph (129 km/h)03h 50m

Fuel, Round Trip and CO2

Estimated fuel cost and emissions for this route.

One-way fuel
10.88 gal
41.2 L · about $45.13
Round trip
$90.26
21.76 gal · 82.4 L
Estimated CO2
96.7 kg one way
Round trip: 193.4 kg / 426 lb CO2, using regular gasoline.
Fuel$/galOne wayRound trip
Regular gas $4.15 $45.13 $90.26
Mid-grade $4.60 $50.00 $100.01
Premium $4.90 $53.27 $106.54
Diesel $4.35 $47.33 $94.66

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 Florida · May 07, 2026

There is no time difference between Key Largo and St. Petersburg. The current time is 21:56:16.

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.