Charlotte, the titular character, is a spider who is a deeply loyal friend. She watches Wilbur from her web in the Zuckermans’ barn and decides that she likes what she sees. She tells Wilbur that she will be his friend and they enjoy each other’s company. She also shows herself to be deeply compassionate despite the fact that she catches bug and drinks their blood to survive. She is wise and knowledgeable, and she uses that knowledge to teach Wilbur and some of the other animals in the barn.

Charlotte is disturbed by the idea of Mr. Zuckerman slaughtering Wilbur, so she contemplates a way to save her friend. She is confident in her skill of spinning webs, knows her strengths as a spider, and believes that she can trick humans. While she does not know enough words to execute her plan completely on her own, she is wise enough to consult the animals in the barn for advice. She also proves herself to be skilled with words as she selects which words are appropriate to spin into her web.

Charlotte is a self-sacrificing friend and repeatedly puts Wilbur before herself. She befriends Wilbur, patiently teaches him, and works hard to save him. She not only comes up with the idea of spinning a word into the web to save Wilbur but works diligently through the night to make it happen. She does so on her own, even consoling Wilbur so he gets a good night sleep while she works. Even when she knows she needs to make her egg sac and will die soon, Charlotte still chooses to see Wilbur through to the end in the attempt to save his life.