Dihybrid Cross Calculator

Expected offspring counts for an AaBb × AaBb cross.

Both dominant (9/16) 9

A_ bb (3/16) 3

aa B_ (3/16) 3

aabb (1/16) 1

Formula: 9 : 3 : 3 : 1 ratio out of 16

Step-by-step with your numbers:

1. Values used:

2. Number of offspring = 16

4. Both dominant (9/16) = 9

5. A_ bb (3/16) = 3

6. aa B_ (3/16) = 3

7. aabb (1/16) = 1

Did we solve your problem today?

The classic two-gene cross between double heterozygotes gives a 9:3:3:1 phenotype ratio.

The math behind it

AaBb × AaBb yields 9 both-dominant : 3 : 3 : 1 both-recessive out of every 16 offspring.

160 offspring → 90 : 30 : 30 : 10.

Independent assortment?

Yes — this assumes the two genes assort independently (on different chromosomes).