The east border was the Salt Sea, even to the end of the Jordan.

The border of the north side was from the bay of the sea at the end of the Jordan. Bible see other translations

“The east border was the Salt Sea.” The east border of the tribe of Judah is easy to delineate. Although any ownership of the Dead Sea would have had to have been negotiated with Moab and Edom, there is no indication that was ever a problem since the water was not drinkable or useful for irrigation, nor did it have any fish.

“The border of the north side.” Judah’s north border is basically the same as Benjamin’s south border as described in Joshua 18.

Commentary for: Joshua 15:5