San Diego to Tijuana distance

San Diego to Tijuana by road

The fastest driving route is 20.1 miles (32.3 km) long and takes about 28 min without stops or traffic. It runs mostly on I-5 (14.9 mi) and the MEX 1 (1.7 mi).

Of the 20.1 mi, 16.0 mi are in the United States and 4.1 mi are in Mexico. That’s an average of 43 mph (70 km/h), and at under two hours you can do it without stopping. The time is OSRM’s estimate with OpenStreetMap data: no traffic and speeds somewhat below the limits, so real trips can differ.

Straight-line distance and bearing

In a straight line, the shortest distance over the Earth’s surface, San Diego and Tijuana are 17.2 miles (27.6 km) apart. That’s the geodesic on the WGS84 ellipsoid, the distance “as the crow flies”.

The road is 17% longer: for every 100 miles in a straight line you drive 117. That’s a normal detour between two cities. Of the 16 US–Canada and US–Mexico driving pairs in this series, it ranks 11th for detour (the average is 22%).

From San Diego, Tijuana lies to the southeast (bearing 149°), and from Tijuana, San Diego lies to the northwest.

Halfway between San Diego and Tijuana

Halfway along the straight line, 8.6 miles (13.8 km) from each city, is the point 32.6090° N, 117.0804° W. It falls near Tijuana (Free and Sovereign State of Baja California, Mexico, pop. 1,922,523), 8.6 mi away.

By road, the halfway point is 10.0 miles (16.2 km) from each city, near Tijuana (Free and Sovereign State of Baja California, Mexico, pop. 1,922,523), 8.3 mi away. The two midpoints almost coincide (0.9 mi apart), because the road doesn’t stray far from the straight line.

Time zone

San Diego and Tijuana share the same time all year: both are on Pacific Time.

The two cities

San Diego has 1.4 million people (Census Bureau estimate for 2025) and Tijuana 1.9 million people (GeoNames).