bioinformatics - Computing Percent Identity between DNA / Amino Acid Sequence

What are some tools where I can input a pair of DNA sequences (or alternatively a pair of Amino Acid Sequences) and compute a percent similarity identity metric between them?

Is BLAST the right algorithm for this or something else?

The context is that a certain patent protects all sequences at least 90% or more identity to a given sequence. I wanted to test some candidate sequences and verify the percent identity metric.

Below I post a patent-snippet where they actually define their identity metric.