13 free calculators · no sign-up · nothing saved

Free health calculators

Simple, friendly tools that do the maths for you. Enter your numbers, get a clear answer in plain English, and see what it means for your health. Every tool runs right in your browser, so nothing you type ever leaves your device.

Heart & circulation

Cholesterol, ratios and training zones. 4

LDL cholesterol

Work out your LDL from a standard lipid panel.

3 inputs Open

Cholesterol ratio

Your total-to-HDL ratio, and what it signals.

2 inputs Open

Heart rate zones

Find your five training zones from your age.

2 inputs Open

Target heart rate

The ideal heart-rate range for your workout.

2 inputs Open

Blood sugar & metabolism

A1c, glucose units and metabolic age. 3

A1c to average blood sugar

Turn your A1c into an estimated average glucose.

1 input Open

Blood sugar converter

Switch between mg/dL and mmol/L in a tap.

1 input Open

Metabolic age

See how your metabolism compares to your age.

4 inputs Soon

Body & composition

Body fat, ratios, macros and protein. 5

Body fat percentage

Estimate body fat with the US Navy method.

3 inputs Open

Waist-to-hip ratio

A 10-second marker of heart-health risk.

2 inputs Open

Body shape

Find your body shape from three measurements.

3 inputs Open

Macro calculator

Daily protein, carbs and fat for your goal.

5 inputs Open

Protein intake

How much protein your body needs each day.

3 inputs Open

Kidney & hydration

Filtration rate and daily water target. 2

eGFR kidney function

Estimate kidney filtration from your creatinine.

3 inputs Open

Water intake

Your daily water target by weight and activity.

2 inputs Open