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PH Functional Class

PH Functional Class: calculated with the published clinical method, with result interpretation. A reference tool that does not replace a doctor's advice.

ℹ Reference calculation based on the published method. It does not replace a clinical examination or a doctor's decision.

PH Functional Class

Ordinary activity causes dyspnoea, fatigue, chest pain or near syncope (1 = yes)
Symptoms with less than ordinary activity (1 = yes)
Symptoms with any activity or at rest (1 = yes)
Signs of right heart failure (1 = yes)
WHO functional class
2
FC is one risk criterion; a comprehensive assessment is needed (6MWD, NT-proBNP, echo, haemodynamics)ESC/ERS 2022 three-strata model (at diagnosis); at follow-up the four-strata model applies, where FC III is intermediate-high riskReference calculation; the decision rests with the physicianPH Functional Class: calculated with the published clinical method, with result interpretation. A reference tool that does not replace a doctor's advice.
WHO class
II
Risk by FC (ESC/ERS 2022)
Low

More about: PH Functional Class

What it calculates

The “PH Functional Class” calculator computes WHO functional class from 4 parameters: ordinary activity causes dyspnoea, fatigue, chest pain or near syncope (1 = yes), symptoms with less than ordinary activity (1 = yes), symptoms with any activity or at rest (1 = yes), signs of right heart failure (1 = yes).

Used by professionals and patients to assess health metrics, dosages, and risks.

Example calculation

With parameters Ordinary activity causes dyspnoea, fatigue, chest pain or near syncope (1 = yes) = 1, Symptoms with less than ordinary activity (1 = yes) = 0, Symptoms with any activity or at rest (1 = yes) = 0, Signs of right heart failure (1 = yes) = 0 the result is 2 (FC is one risk criterion; a comprehensive assessment is needed (6MWD, NT-proBNP, echo, haemodynamics)).

How to use

  1. Enter ordinary activity causes dyspnoea, fatigue, chest pain or near syncope (1 = yes), symptoms with less than ordinary activity (1 = yes), symptoms with any activity or at rest (1 = yes) and signs of right heart failure (1 = yes) — each field above is adjustable with a slider.
  2. WHO functional class is calculated automatically as you type.
  3. Check the worked example below to see the formula applied to real numbers.
  4. Copy the result or bookmark this calculator.

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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.

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