QUICK ANSWER
"As long as" is a phrase which is often translated as "siempre y cuando", and "as far as" is a phrase which is often translated as "tan lejos como". Learn more about the difference between "as long as" and "as far as" below.
as long as(
ahz
lang
ahz
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. siempre y cuando
As long as you finish your homework, you can go out to play.Siempre y cuando termines tu tarea, puedes salir a jugar.
b. siempre que
I don't care where we live as long as we're together.No me importa dónde vivimos, siempre que estemos juntos.
c. con tal de que
She accepts everyone's opinion, as long as they agree with her.Acepta la opinión de todos, con tal de que estén de acuerdo con ella.
2. (while)
a. mientras
I'm not leaving the house as long as it's raining.No salgo de casa mientras esté lloviendo.
3. (since)
a. puesto que
As long as you are going to the store, can you bring me some milk?Puesto que vas a la tienda, ¿me puedes traer leche?
a. tan largo como (length)
I saw a crocodile as long as a car in Egypt.Vi un cocodrilo tan largo como un coche en Egipto.
as far as(
ahz
far
ahz
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (distance)
a. tan lejos como
You're in Boston? That's not as far as I thought.¿Estás en Boston? No está tan lejos como pensé.
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
a. en cuanto a
As far as height goes, this is one of the biggest mountains in Utah.En cuanto a la altura, ésta es una de las montañas más grandes de Utah.