Compatibility
Calculate Compatibility instantly with the exact formula and a worked example. Free online calculator — no signup.
Compatibility
Donor (0=O, 1=A, 2=B, 3=AB)
Recipient
Compatibility
1
More about: Compatibility
What it calculates
The “Compatibility” calculator computes Compatibility from 2 parameters: donor (0=o, 1=a, 2=b, 3=ab), recipient.
Used by professionals and patients to assess health metrics, dosages, and risks.
Example calculation
With parameters Donor (0=O, 1=A, 2=B, 3=AB) = 0, Recipient = 0 the result is 1.
How to use
- Enter the parameter values — every field above is adjustable with a slider.
- The result and related metrics are calculated automatically as you type.
- Use the additional metrics shown (if any) where needed.
- Copy the result or bookmark the page.
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FAQ
How is BMI calculated?
BMI = weight (kg) / height (m)². Example: 70 kg / (1.75 m)² = 22.9. The WHO normal range is 18.5–24.9; below that is underweight, 25–29.9 is overweight, and 30+ is obese.
Is BMI accurate for everyone?
No. BMI does not distinguish muscle from fat, so athletes may show a high BMI with low body fat. It is also less reliable for teenagers, pregnant people, older adults, and very tall or short individuals.
What are the BMI categories?
Underweight: below 18.5. Normal: 18.5–24.9. Overweight: 25–29.9. Obese class I: 30–34.9; class II: 35–39.9; class III: 40+.
What is a better measure than BMI?
Body fat percentage, waist-to-height ratio (aim for under 0.5), and waist circumference give a clearer picture of health than BMI alone.