Count the total number of copies of the allele in the population
Count the total number of all alleles for that gene in the population
Divide the allele count by the total allele count
Use the formula: allele frequency = number of copies of the allele / total number of alleles
For a diploid population, total alleles = 2 × number of individuals
For genotype counts, count each allele present in each genotype
Check that all allele frequencies for the gene add up to 1
Convert to percentage if needed by multiplying the frequency by 100