Health Calculators
Free, accurate health calculators for fitness, nutrition, body composition, medical assessments, and military fitness. Results update instantly — no sign-up required.
Fitness & Body
Calculators for strength training, cardio, body composition, and nutrition goals.
Estimates your one-rep maximum from any set using Epley, Brzycki, and more formulas.
Open calculator →Estimates bench press 1RM and training weights with strength standards by bodyweight.
Open calculator →Calculates daily protein, carbs, and fat targets based on TDEE, activity, and goal.
Open calculator →Predicts next 6 periods, ovulation date, and fertile window from your menstrual cycle data.
Open calculator →Calculates keto macros with a 5/25/70 carb/protein/fat split for ketogenic diets.
Open calculator →Estimates calories burned running by weight, distance, pace, incline, and surface.
Open calculator →Converts step count to miles, km, and calories burned — with stride length from height.
Open calculator →Estimates VO2 max from the Cooper 12-min run, Rockport walk, or non-exercise method.
Open calculator →Restaurant Nutrition
Build your meal and see calories, protein, carbs, fat, and sodium — before you order.
Estimates calories and macros for a custom Chipotle bowl, burrito, or tacos.
Open calculator →Estimates calories, sugar, and caffeine for any custom Starbucks drink and food.
Open calculator →Estimates calories and macros for a custom Subway sandwich or wrap.
Open calculator →Tracks calories and macros for a custom McDonald's meal order.
Open calculator →Tracks calories and macros for any Taco Bell menu item combination.
Open calculator →Estimates calories and macros for a custom Cava Mediterranean grain bowl.
Open calculator →Peptide Calculators
Dosage and reconstitution calculators for research peptides including GLP-1 agonists, healing peptides, and growth hormone secretagogues.
Calculates syringe units and volume for ipamorelin doses in mcg — the most popular GHRP.
Open calculator →Calculates syringe units and volume for CJC-1295 (no DAC) doses — the classic ipamorelin stack partner.
Open calculator →Calculates syringe units and volume for retatrutide weekly doses from vial concentration.
Open calculator →Calculates syringe units and volume for semaglutide weekly doses from vial concentration.
Open calculator →Calculates syringe units and volume for tirzepatide weekly doses from vial concentration.
Open calculator →Medical & Clinical
Clinical scoring tools and medical reference calculators. For informational use only — always consult a healthcare provider.
Estimates eGFR using CKD-EPI 2021 and MDRD equations and CKD stage.
Open calculator →Converts between A1C % and estimated average glucose (eAG) in mg/dL or mmol/L.
Open calculator →Calculates body surface area using DuBois, Mosteller, Haycock, and Gehan-George.
Open calculator →Adjusts total calcium for albumin level and classifies hypo/hypercalcemia.
Open calculator →Calculates absolute neutrophil count from WBC and differential, with neutropenia tier.
Open calculator →Calculates mg/kg doses, liquid volumes, and IV infusion rates for drug administration.
Open calculator →Calculates IV flow rate in mL/hr or gtts/min from volume, time, and drop factor.
Open calculator →Estimates ethyl glucuronide detection window in urine from drinks consumed.
Open calculator →Military Fitness
Official Army and USMC fitness test scoring calculators.
Calculates Army body fat % using the AR 600-9 circumference method with pass/fail.
Open calculator →Scores all 6 Army Combat Fitness Test events and total with pass/fail by age and sex.
Open calculator →Scores USMC Physical Fitness Test events and classifies First/Second/Third Class.
Open calculator →Scores Army Fitness Test events including deadlift, push-ups, and 2-mile run.
Open calculator →Checks weight against Army AR 600-9 screening tables and flags for tape test.
Open calculator →Our free health calculators cover four very different needs under one roof: everyday fitness and nutrition planning, evidence-based clinical scoring, peptide dosing math, and official military fitness test scoring. They are used by lifters dialing in macros, nurses checking an IV drip rate, and soldiers prepping for a record test. Every tool uses the published formula behind the number — Mifflin-St Jeor for calories, CKD-EPI 2021 for kidney function, AR 600-9 for Army body fat — so you can see exactly how the result was derived rather than trusting a black box.
From training goals to clinical thresholds
On the fitness side, the numbers translate directly into programming. A lifter who benches 225 lb for 5 reps has an estimated one-rep max of about 253 lb by the Epley formula, which our 1 rep max calculator uses to set working percentages. Cutting weight? The macro calculator splits a 2,000-calorie target into roughly 150 g protein, 200 g carbs, and 56 g fat on a balanced 30/40/30 plan. On the clinical side, an eGFR of 60 mL/min/1.73m² marks the boundary between normal and Stage 3 chronic kidney disease — the kind of threshold our medical tools flag automatically.
Dosing and test scoring you can verify
The peptide dosage calculator converts a target dose in micrograms into insulin-syringe units after reconstitution — for example, a 250 mcg dose from a 5 mg vial mixed with 2 mL of bacteriostatic water draws to 10 units on a U-100 syringe. Clinical and dosing tools here are for informational use only and never replace a healthcare provider. Pick the calculator that matches your goal, enter your own numbers, and the result updates instantly with the formula shown.