"Por" vs. "Para"

Knowing when to use "por" and when to use "para" can be challenging! In general, both words can be substituted for the English word, "for", but not always.

"Por" usually implies that something is done in the name of something or someone, or that some sort of exchange is happening. 

Use “por” to talk about:
going through or around an area
a reason for an action or justification
communication and transportation
exchange or substitution
provide a time frame for
percentages

"Para" usually implies that something is being done for something or someone. If it’s before a verb, it means "in order to...". 

Use “para” to talk about:
a purpose or goal
destinations
deadlines
the recipient of something
to be in the employ of
opinions
standards

Unfortunately, there is no single rule for when to use either of these versatile prepositions; you just have to remember them! 

Here are some lessons and articles that will give you some more information on all of the different uses of "por" and "para":
https://app.fluencia.com/#skills/es/51c9bc676be86d425e0001cf/lesson
https://app.fluencia.com/#skills/es/51fc07903a9ae29a5300010e/lesson
https://app.fluencia.com/#skills/es/52cc7d00e152c56045000007/lesson
https://app.fluencia.com/#skills/es/52cc7d87e152c56045000008/lesson
http://www.spanishdict.com/topics/show/10