Main tool: snp-dists
Full documentation: https://github.com/tseemann/snp-dists
Convert a FASTA alignment to SNP distance matrix
# run snp-dists on the test alignment file bundled with snp-dists
wget -q https://raw.githubusercontent.com/tseemann/snp-dists/refs/heads/master/test/good.aln
snp-dists good.aln > good.out
cat good.out
seq1 seq2 seq3 seq4
seq1 0 1 2 3
seq2 1 0 3 4
seq3 2 3 0 4
seq4 3 4 4 0