# Modular hashing confusion

I am trying to learn about basic hashing using the modulo operator and am a bit confused. In the text that I am reading, it says that the modulo operator can be used to accept an input of any length and return a fixed-size output. However, take 1mod11 = 1 and 21mod11 = 10. The first equation yields a one-digit number and the second equation yields a two-digit number, how is it returning a fixed-sized output? Yes, a trivial question, but it's just not clicking for me - anyone care to explain?

The output can always be represented by $$n$$ or fewer digits.