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Punnett Square Calculator

Health & Body

Gene cross → genotype & phenotype ratios

Quick Answer

Punnett Square Calculator: Gene cross → genotype & phenotype ratios. Punnett Square Calculator uses standard health formulas to compute accurate results instantly.

Father genotype

Mother genotype

Trait presets

A
a
A
AA
Aa
a
Aa
aa

Aa × Aa → offspring

Genotype ratio

AA（25%）1
Aa（50%）2
aa（25%）1

Phenotype ratio

Double eyelid75%（3:1）
Single eyelid25%（1:3）
  • Mendel's law of segregation: each parent passes one allele per gene. Aa produces A and a gametes 1:1, so offspring genotypes combine at random.
  • Each child is an independent event. Two brown-eyed parents (Aa) having one blue-eyed child does not change the next child's odds — still 25%.
  • Common dominant traits: double eyelid, detached earlobe, tongue rolling, right-handedness; recessive: single eyelid, attached earlobe, left-handedness.
  • ABO blood type is codominant (Iᴬ and Iᴮ both express) — use the blood type calculator instead.
  • Incomplete dominance (e.g. snapdragon flower) gives 1:2:1 phenotype; sex-linked traits (red-green colorblindness) need X-chromosome models not covered here.
  • Ratios are probabilities for large samples only — real families of 2–3 kids can deviate a lot from 3:1.

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How to Use

  1. Enter body metrics: fill height, weight, age etc. as prompted by the Punnett Square Calculator.
  2. Read value and grade: results appear instantly with an authority-based classification.
  3. Check reference tables: confirm your range and healthy targets against the tables on this page.
  4. Back-solve your goal: adjust inputs to see what it takes to reach a target.

Key Points

  • Punnett Square Calculator is a free online health tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: Gene cross → genotype & phenotype ratios.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Punnett Square Calculator formula

Punnett Square Calculator uses standard health formulas to compute accurate results instantly.

FAQ

How do I use the Punnett Square Calculator?
Open the page and fill in the input fields — results update automatically. Gene cross → genotype & phenotype ratios.
Are the results accurate?
Results follow published international standards (WHO, ACE, IOM) and are for reference only.
Can this replace medical advice?
No. Always consult a qualified healthcare professional for health decisions.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Does it work on mobile?
Yes. The responsive design works on all devices.

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Source & Updates

Based on WHO, ACE, IOM and other published international standards. Last updated: 2025-07

Authoritative sources:

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Punnett Square Calculator[EB/OL]. https://www.yijiansuan.com/en/c/health/punnett

Results provided by this tool are for reference only and do not constitute professional advice.