1. A computer-implemented method for detecting character encodings of text streams, at least a portion of the method being performed by a computing device comprising at least one processor, the method comprising: identifying a request to identify a character encoding of a text stream; dividing the text stream to identify a plurality of n-grams within the text stream; identifying a plurality of vectors within a vector space, each vector representing a potential character encoding by a plurality of expected n-grams within the potential character encoding; generating, based at least in part on the plurality of n-grams within the text stream and based at least in part on an inverse frequency of appearance of each of the plurality of n-grams within the plurality of vectors, a representative vector describing the text stream; identifying the character encoding of the text stream based on identifying a similarity between the representative vector and a neighboring vector within the plurality of vectors representing the character encoding.