Health calculators
Body metrics, energy needs, and pregnancy timing tools.
Health calculators on pancalc are built for education and screening context — BMI, BMR, calorie targets, pregnancy dating, and related metrics. Each page explains which inputs drive the result and what the output does not tell you.
These tools help you prepare for conversations with clinicians, track trends over time, or verify homework problems. They are not diagnostic instruments and cannot account for your full medical history, medications, or individual risk factors.
Read the limitations section on every health calculator before acting on a number. When a result affects care decisions, discuss it with a qualified healthcare provider who knows your situation.
13 calculators
Blood Alcohol Content (BAC) Calculator
Widmark-estimate BAC from drinks, body weight, sex, and hours since first drink. Use the calculator above. Free browser tool. Free browser tool.
BMI Calculator
Calculate body mass index from height and weight, or solve for a target weight or height with cautious screening interpretation. Free browser tool.
BMR Calculator
Estimate basal metabolic rate in calories per day from age, sex, height, and weight using the Mifflin–St Jeor equation. Free browser tool.
Body Surface Area (BSA) Calculator
DuBois & DuBois body surface area from height and weight. Use the calculator above. Use the calculator above. Free browser tool. Free browser tool.
Calorie Calculator
Estimate BMR and daily calorie expenditure from age, sex, height, weight, and an activity factor using Mifflin–St Jeor. Free browser tool.
eGFR (CKD-EPI simplified) Calculator
Estimate glomerular filtration rate from creatinine, age, and sex using the calculator’s simplified CKD-EPI-style equation. Free browser tool.
HOMA-IR Insulin Resistance Calculator
Estimate HOMA-IR from fasting glucose and fasting insulin with a clear formula, interpretation guidance, and medical limitations. Free browser tool.
Ideal Body Weight Calculator
Devine formula ideal body weight from height and sex. Use the calculator above. Use the calculator above. Free browser tool. Free browser tool.
IV Drip Rate & Infusion Calculator
Estimate an IV flow rate in drops per minute and mL per hour from volume, infusion time, and tubing drop factor. Free browser tool.
Ovulation & Fertility Window Calculator
Estimate ovulation day and fertile window from cycle length and last period day. Use the calculator above. Free browser tool. Free browser tool.
Pregnancy Due Date Calculator
Estimate a due date and conception date from the first day of a last menstrual period using the standard 280-day convention. Free browser tool.
TDEE & Macro Calculator
Mifflin-St Jeor TDEE with macro gram targets from calorie split percentages. Use the calculator above. Use the calculator above. Free browser tool.
Waist-to-Hip Ratio Calculator
Calculate waist-to-hip ratio from matching measurements and understand this body-fat distribution screening measure with examples.