Publisher and responsibility
BloodTypeCalc.com is operated by Bobby Litmon, the publisher responsible for the site and its correction process. Educational pages use the BloodTypeCalc.com byline. Publisher identity does not imply that a page has received independent clinical review; our editorial policy describes the review status.
What this site is
BloodTypeCalc.com is an independent educational resource. We build calculators that apply the standard ABO and Rh inheritance model so anyone can explore which blood types a child may have, which parent types could produce a given child, and how blood types relate for transfusion. Alongside the tools we publish reference articles written in plain language and checked against primary sources such as the American Red Cross, MedlinePlus and ACOG.
Who it is for
Expectant parents curious about their baby's possible blood type, students learning genetics, blood donors wanting to understand compatibility, and anyone who has just learned their type and wants to know what it means. It is not intended for clinical decision-making.
How the calculators work
Our tools run entirely in your browser, and the blood types you choose are not sent to our servers or saved. They are not all the same kind of tool. The inheritance calculators (baby, parent, and Punnett square) enumerate every parental genotype consistent with the types you choose and report a range of Mendelian probabilities rather than a single averaged number. The donation compatibility tools apply the standard ABO/RhD red-cell and ABO plasma transfusion rules. The rarity tool looks up published U.S. frequency estimates. The calculation logic is covered by automated tests. Read the editorial policy for how content is reviewed. The calculator methods page shows the genotype assumptions, worked examples and the limits of software checks.
Limits
The standard model does not account for rare variants (Bombay phenotype, cis-AB, weak D) and results are never a substitute for laboratory testing or medical advice. Our tools should not be used to draw conclusions about parentage. See the medical disclaimer.
Funding
The site is free to use and supported by advertising. Ads are clearly labelled and never influence the content of our calculators or articles.
Contact
Questions, corrections or feedback are welcome. Visit the contact page to send a message or report an error through the form. Include the affected page and the detail you want us to check, without sending identifying medical records.