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Free health calculators, minus the jargon.

Cholesterol, blood sugar, heart rate, body and hydration. Punch in your numbers, get a straight answer, and see what it actually means for you, in plain English.

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Blood sugar & metabolism

A1c, glucose units and metabolic age. 3

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A tape measure showing correct waist and hip landmarks beside a waist-to-hip ratio calculation

Waist-to-hip ratio chart: how to measure and read your result

Measure waist and hips consistently, calculate the ratio, and understand sex-specific risk bands and their limitations.

Sheenam Midha 8 min read
Men across adult age groups beside a body-composition range, tape measure, and strength equipment

Healthy body fat percentage for men by age

See commonly cited male body-fat ranges by age and learn how muscle mass, health markers, and measurement error should shape interpretation.

Sheenam Midha 8 min read
Male and female body-composition silhouettes beside broad essential, athlete, fitness, and general ranges

Body fat percentage chart for men and women

Compare body-fat categories for men and women, understand essential fat and athlete ranges, and see how measurement error changes interpretation.

Sheenam Midha 8 min read
Women across adult age groups beside a body-composition range and measuring tools

Healthy body fat percentage for women by age

See commonly cited body-fat ranges for women by age, how menopause and measurement method affect interpretation, and why one reading is not a diagnosis.

Sheenam Midha 8 min read
A walker and runner comparing sustainable heart-rate intensity with total energy use over time

Target heart rate for fat loss: what the fat-burning zone misses

Calculate a target heart-rate range, understand fat oxidation versus fat loss, and choose exercise intensity you can sustain.

Sheenam Midha 8 min read
Five colored exercise intensity bands arranged around a heart-rate trace for different ages

Heart rate zones by age: a complete training chart

See five heart-rate zones by age, calculate each range, and learn how resting heart rate, medicines, and exercise type change the estimate.

Sheenam Midha 9 min read
A relaxed runner speaking comfortably while a heart-rate zone band changes across age groups

Zone 2 heart rate by age: chart and better ways to estimate it

Use an age-based Zone 2 chart as a starting point, then refine it with the talk test, resting heart rate, or measured thresholds.

Sheenam Midha 8 min read
An exercise heart-rate trace falling during the first two minutes of recovery beside a stopwatch

Heart rate recovery chart: what your 1- and 2-minute drop means

Measure heart rate recovery consistently, compare one- and two-minute drops, and understand why protocol and symptoms matter more than one cutoff.

Sheenam Midha 8 min read
Total cholesterol, HDL, and triglyceride values entering the Friedewald calculated LDL equation

Friedewald formula: how calculated LDL cholesterol works

See the Friedewald LDL formula in mg/dL and mmol/L, work through examples, and learn when the estimate becomes unreliable.

Sheenam Midha 7 min read