About CrossCalc

CrossCalc is a small set of free genetics tools for anyone learning or teaching Mendelian inheritance.

What we do

Working out a dihybrid Punnett square by hand takes time, and one misplaced allele throws off the whole ratio. CrossCalc does the bookkeeping. It lists every gamete, fills in the square and counts each genotype and phenotype. That way you can check homework, build worksheets or explore “what if” crosses in seconds.

• Monohybrid cross calculator: one gene, 2×2 square
• Dihybrid cross calculator: two genes, 4×4 square
• Trihybrid cross calculator: three genes, 8×8 square
• Blog: plain-English articles on the concepts behind each tool

How the calculators work

Every result follows the standard textbook model: complete dominance and independent assortment. The calculation engine is tested against known results, including 3:1 and 1:2:1 for a monohybrid cross, 9:3:3:1 for a dihybrid F2, 1:1:1:1 for a test cross and the 27:9:9:9:3:3:3:1 trihybrid classes. Everything runs in your browser. Nothing you enter is sent anywhere.

Corrections and suggestions

If you spot an error or would like a feature, such as a new cross type, get in touch. Teachers’ suggestions are especially welcome.

CrossCalc is run by CrossCalc.