What is the largest number of characters that can be represented using ASCII?

The largest number of characters that can be represented using ASCII is 128.

In ASCII (American Standard Code for Information Interchange), there are a total of 128 characters that can be represented. These characters include uppercase and lowercase letters, digits, punctuation marks, special characters, and control characters. The ASCII character set uses 7 bits to represent each character, allowing a maximum of 128 unique characters.