Difference between Unpretentious and Unostentatious

What is the difference between Unpretentious and Unostentatious?

Unpretentious as an adjective is simple, humble, not pretentious while Unostentatious as an adjective is not ostentatious; simple; unpresuming.

We hope you now know whether to use Unpretentious or Unostentatious in your sentence.