Karate can be effective and good for both self-defense and a real-life fighting situation with it's equal drawbacks ie. Single karate techniques as well as the low stances and rigid footwork, which allows for quick and flexible movement, can be fairly effective in a real fight or for self-defense.

Is karate effective in a street fight?

Traditional martial arts have their roots in combat tactics used on the battlefield. Many Japanese arts are based on the fighting techniques of the samurai. Modern teaching methods may have softened the application of these techniques, but they can still be effective in street fights.

Does karate work in the street?

Karate in itself is not meant for street fighting. If you want to learn how to hold your own in a street fight. Go to a MMA gym, boxing and Muay Thai are good too. The point here is fullcontact sparring against a resisting opponent.