Run your own numbers
Weight and GLP-1
BMI calculator
Most weight-loss programmes screen on BMI before they will prescribe. This is the number they will use.
A screening number, not a diagnosis. It does not distinguish muscle from fat, and it reads high for muscular builds.
Calorie and BMR calculator
How many calories your body burns at rest, and a sensible daily target for steady weight loss.
Mifflin-St Jeor equation. On a GLP-1 you will likely undershoot this without trying; treat it as a floor-check, not a target to chase.
Protein target calculator
Rapid weight loss burns muscle unless protein stays high. This matters double on a GLP-1, when appetite disappears.
Low protein intake is a common complaint in GLP-1 patient discussions, and clinicians routinely flag it alongside muscle loss. Spread it across the day; appetite suppression makes one big meal unrealistic.
Macro split calculator
Turn a daily calorie target into grams of protein, carbohydrate and fat.
A starting split, not a prescription. Protein is the one worth protecting on a GLP-1; the other two are preference.
Weight loss timeline
How long a target is likely to take at a realistic rate, and what the trial percentages would put you at.
Trial averages are not promises: individual response varies widely, and results depend on staying on treatment. Faster than about 2 lb a week usually costs muscle.
Weight loss progress
Percentage lost is the number trials report and clinicians track, and it is a fairer measure of progress than pounds alone.
Five percent is the threshold at which metabolic benefits typically start to show in the literature.
Ideal body weight range
A reference range for your height, useful for sanity-checking a goal weight before you set one.
Devine formula plus the healthy BMI range. A reference point, not a target anyone has to hit; frame and muscle both shift what is right for you.
Dose to syringe units converter
Compounded vials are dosed in mg, insulin syringes in units. Dose-to-volume conversion is a frequent source of confusion when a prescription is written in milligrams but supplied in a fixed concentration.
Educational math only. Always confirm your dose and draw with the dispensing pharmacist; concentrations differ between pharmacies and even between refills.
Body measurements
Waist-to-hip ratio
A better cardiovascular risk signal than BMI alone, and the number some programmes screen on alongside it.
Measure the waist at the navel and hips at the widest point. WHO cut-offs; a tape measure beats a bathroom scale for tracking GLP-1 progress.
Waist-to-height ratio
A single-number check that works across builds better than BMI, with one easy rule: keep your waist under half your height.
Measure at the navel, not at your belt line. Under 0.5 is the widely used cut-off for adults.
Body fat estimate
A tape-measure estimate of body fat percentage, which tracks GLP-1 progress better than the scale when muscle is changing too.
US Navy circumference method. Accurate to within a few points for most people; a DEXA scan is the reference standard.
Metabolic and diabetes
HbA1c and average glucose
Convert between the HbA1c on your lab report and the average glucose it represents, in either unit.
ADAG equation. HbA1c reflects roughly the last three months and can read falsely low with anaemia or recent blood loss.
Glucose unit converter
US labs report glucose in mg/dL, most of the rest of the world in mmol/L. Useful when a programme, a meter and a lab report disagree.
Straight unit conversion, divide or multiply by 18.0182. It changes nothing clinically.
HOMA-IR insulin resistance
Estimates insulin resistance from a fasting glucose and fasting insulin, the pair many programmes order before prescribing.
Both values must be fasting and drawn at the same time. Thresholds vary between labs and populations; treat this as a discussion point with a clinician, not a diagnosis.
CGM time in range
Turn the hours your monitor spends in each band into the percentages clinicians actually use.
Consensus targets for most adults are above 70 percent in range and under 4 percent below it. Your own targets may differ; pregnancy and older age change them.
Carb servings per meal
Turn a daily carbohydrate target into servings per meal, the unit most diabetes education uses.
One serving is 15 g of carbohydrate. If you use insulin, your ratio is set with your care team and overrides any general figure.
Heart and blood pressure
Blood pressure average
Programmes that screen on blood pressure want an average of several readings, not the one that worried you.
Take readings seated, arm supported, after five minutes rest. A single high reading is rarely the point; the pattern is.
Mean arterial pressure
The averaged pressure across a full heartbeat, which some programmes record alongside the usual two numbers.
Standard estimate from a cuff reading. Interpretation belongs with a clinician who knows your history.
Target heart rate zones
The zones to aim for when a programme tells you to add cardio, worked from your age and resting rate.
Karvonen method using heart rate reserve. Beta blockers and some other medications blunt heart rate, which makes these zones unreliable; ask your prescriber.
Cholesterol ratio and LDL
Work out LDL and the total-to-HDL ratio from a standard lipid panel, the two numbers a clinician reads first.
Friedewald equation, which is unreliable when triglycerides exceed 400 mg/dL. Ratios are a screening signal, not a treatment decision.
Cholesterol unit converter
US panels report cholesterol in mg/dL and most other countries in mmol/L, which makes comparing a result across borders needlessly hard.
Cholesterol and triglycerides use different conversion factors, so pick the right one.
Kidney function
Kidney function estimate
Several weight and diabetes medications are dose-adjusted or avoided below certain kidney function levels. This is the number that decides it.
CKD-EPI 2021 equation, which no longer uses a race coefficient. A single reading is not a diagnosis: kidney function is assessed over time and alongside urine albumin.
Creatinine clearance
The older kidney measure that many drug labels still use for dose adjustment, so it is often the one a pharmacist asks about.
Cockcroft-Gault, which uses actual body weight and can mislead at extremes of weight. Your prescriber decides which measure applies to your medication.
Urine albumin to creatinine ratio
The urine test that catches early kidney change, often ordered alongside kidney function before a diabetes or weight medication is started.
A single raised result is usually repeated before it means anything: exercise, fever and infection all push it up temporarily.
Cost
What a year actually costs
Programmes quote a monthly headline. Add the medication, the labs and the renewal price and the real number is usually different.
Advertised prices change often and intro pricing rarely lasts. Ask what the renewal rate is before you commit to a plan.
Cost per pound lost
A blunt way to compare two programmes that quote very different monthly prices.
Only as good as the loss estimate you feed it, and weight loss is not linear. Useful for comparing options, not for predicting your own result.
Insurance or cash pay, which is cheaper
Going through insurance is not automatically cheaper. Deductibles, copays and prior authorisation can make a cash-pay programme the better deal.
Coverage is never something a programme can promise: plans decide, prior authorisation is routine for GLP-1 medicines, and denials are common. Confirm with your own plan before choosing.
Womens health and lifestyle
Due date estimator
Estimated due date and current stage from your last period. Relevant here because most weight medications are stopped in pregnancy.
Naegele rule, assuming a 28 day cycle. A dating scan is more accurate. GLP-1 medications are stopped before a planned pregnancy; ask your prescriber how long before.
Ovulation window
The likely fertile window from your cycle, useful whether you are trying to conceive or timing a birth control switch.
Calendar estimate only. Cycles vary month to month, and this is not a contraceptive method. Ask a clinician before stopping any birth control.
Pack-year calculator
Smoking history in the unit clinicians record it in, and the number that decides lung screening eligibility.
One pack-year is 20 cigarettes a day for a year. US screening guidance currently starts at 20 pack-years for adults aged 50 to 80 who smoke or quit within 15 years.
Stopping smoking, what it saves
What the habit costs over a year, next to what a telehealth quit programme costs.
Money only. The health case is separate and much stronger; prescription quit medications are covered by many plans.