Body Composition
Visceral fat risk, lean tissue mass and frame load.
Waist-to-height ratio calculator for longevity
Enter your waist and height. Measure at the navel, relaxed and not pulled in, with the tape level all the way round.
Why it matters for longevity. Central fat is the depot that drains directly to the liver and drives metabolic disease. This ratio outperformed BMI for predicting cardiovascular and metabolic risk across roughly 300,000 people, and it needs nothing but a tape measure.
Waist-to-Height Ratio →Body fat percentage calculator for longevity
Estimates body fat from circumference measurements using the US Navy method, then places the result in the ACE classification for your sex. It reports the category rather than a leanness rank, because lower is not automatically better for this marker.
Why it matters for longevity. Body composition is one of the six scored domains, and the relationship with mortality is a curve rather than a line. Both ends carry cost: too high drives metabolic risk, too low disrupts hormones and bone density.
Body Fat Percentage and Longevity →Cardiovascular Health
Hemodynamics, autonomic balance and aerobic efficiency.
VO2 Max calculator for longevity
Pick whichever test you can actually do. The step test needs no running at all; the others need a track, a treadmill or a measured route. Each estimates the same number by a different route.
Why it matters for longevity. Cardiorespiratory fitness carries a steeper association with all-cause mortality than any other marker tracked here, and the largest single drop in risk sits between the least fit group and the one immediately above it. Getting off the bottom matters far more than approaching the top.
VO2 Max →Compound Strength
Relative strength across the four major lifts.
One-rep max calculator
Estimates your one-rep max from a submaximal set using the Epley formula, and gives the training load at every rep range below it. Accuracy drops above about ten reps, and the tool says so rather than pretending otherwise.
Why it matters for longevity. Strength predicts all-cause mortality independently of cardiovascular fitness. You need a maximum to know which training loads to use, and estimating it from a submaximal set avoids the injury risk of testing a true one-rep max.
1RM and Rep-Max Percentages →Strength standards calculator for longevity
Squat, bench, deadlift and overhead press against your bodyweight, interpolated for your exact weight and adjusted by an age-decline curve. Scoring caps at Advanced with no credit for Elite, because strength tracks longevity only up to a point.
Why it matters for longevity. Muscular strength predicts all-cause mortality, with the strongest signal at the weak end of the distribution. That shape is why the scoring caps at Advanced: getting off the floor of the range matters enormously, and chasing the ceiling adds injury risk without clear benefit.
Strength Standards →Functional Capacity
Movement quality, balance, endurance, grip and cognitive speed.
Protein target calculator for longevity
Your daily target in grams, from bodyweight and age, plus what that looks like split across three meals. Targets come from the ISSN position stand for active adults and the PROT-AGE recommendations for over-65s, which are two different research bodies answering two different questions.
Why it matters for longevity. Muscle mass is the tissue you lose fastest with age and the hardest to rebuild once gone. Protein intake is the dietary lever that determines whether resistance training produces new tissue or merely maintains what is there, and requirements rise rather than fall after 65.
Protein Intake for Longevity →Sitting-Rising Test scorer for longevity
Tick the supports you needed sitting down and standing up. The score is calculated from the published deduction rules, starting at ten and subtracting for each hand, forearm, knee or leg used.
Why it matters for longevity. One of the strongest single-test mortality predictors published. Each point lost was associated with roughly 21 percent higher all-cause mortality, and scores below 8 carried five to six times the risk of scores of 8 to 10. It measures the strength, balance and mobility that determine whether you can get off the floor unaided at eighty.
The Sit-to-Stand Test →6-minute walk test calculator for longevity
Enter your age, sex, height and weight to get your predicted distance, then add what you actually walked to see it as a percentage of that prediction.
Why it matters for longevity. Functional endurance is what daily life actually asks of you, and this test measures the cardiovascular, pulmonary and muscular systems working together rather than any one in isolation. Falling below 80 percent of predicted is the clinical signal that capacity is reduced.
The 6-Minute Walk Test →Metabolic Health
Glucose tolerance, insulin sensitivity and energy regulation.
HbA1c calculator and longevity ranges
Three-month average blood sugar. The optimized bands sit entirely inside what a laboratory reports as normal, and they have a floor as well as a ceiling, because a very low reading can reflect anemia rather than good control.
Why it matters for longevity. Chronic glucose elevation damages blood vessels for years before diabetes is diagnosed, and vascular damage is the shared pathway into cardiovascular disease and dementia. HbA1c carries the joint-heaviest weight in the metabolic domain.
HbA1c and Longevity →Triglycerides calculator and longevity ranges
Enter your result to see which band it falls in. Fast for 9 to 12 hours and avoid alcohol for at least 48 hours beforehand, or the reading will reflect the weekend rather than your baseline.
Why it matters for longevity. A marker of metabolic state rather than just a lipid, closely tied to insulin resistance and liver fat. It is also the fastest-responding lipid, which makes it the one to retest first when checking whether a change is working.
Triglycerides →HOMA-IR calculator and longevity ranges
Enter fasting glucose and fasting insulin from the same blood draw. Both appear on a routine fasting panel, though insulin often has to be requested.
Why it matters for longevity. Insulin resistance underlies metabolic syndrome, type 2 diabetes and much of cardiovascular risk, and it develops for years while glucose stays normal. Combining glucose with insulin catches it far earlier than glucose alone.
Insulin Resistance, Explained →Metabolic syndrome checker for longevity
Tick each criterion that applies, including any you are currently treated for. The count is what determines whether the definition is met.
Why it matters for longevity. The five criteria cluster because they share an underlying cause, and meeting three substantially raises risk of cardiovascular disease and diabetes. Most of the cluster is reversible, which makes catching it at one or two criteria worthwhile.
Metabolic Syndrome, Explained →Fasting insulin calculator and longevity ranges
Enter your fasting insulin result. It is measured in μU/mL on most panels, and it is worth checking the unit before comparing against these bands.
Why it matters for longevity. The earliest detectable signal of metabolic dysfunction, often rising a decade before glucose moves. It is also the marker most often missing from a standard panel, so it usually has to be requested by name.
Insulin Resistance, Explained →Fasting glucose calculator and longevity ranges
Enter your fasting glucose in mg/dL, taken after a 9 to 12 hour fast.
Why it matters for longevity. A late signal compared with insulin, but the one clinical medicine acts on. The optimized band has a floor as well as a ceiling, because unusually low fasting glucose is not itself a marker of health.
Continuous Glucose Monitors →Systemic Health
Silent inflammation, organ function and nutrient status.
ApoB calculator and longevity ranges
The count of atherogenic particles, which tracks cardiovascular risk more directly than the amount of cholesterol those particles carry. A standard lipid panel will not include it unless you ask.
Why it matters for longevity. Every atherogenic particle is a chance to lodge in an artery wall, and ApoB counts the particles rather than the cholesterol inside them. Cumulative lifetime exposure is what drives atherosclerosis, so the number matters decades before an event.
ApoB vs. LDL Cholesterol →Lp(a) calculator and longevity ranges
Enter your result against the National Lipid Association cut-off. Check your units first: some laboratories report mg/dL rather than nmol/L, and the two do not convert with a single reliable factor.
Why it matters for longevity. An independent cardiovascular risk factor that is roughly 90 percent genetic, making it the one marker here that effort barely touches. Knowing it changes how aggressively everything you can control is worth managing.
Lipoprotein(a) →hs-CRP calculator and longevity ranges
A general inflammation marker. Recent infection, injury or a hard training session all raise it, so a single elevated reading means little without a retest under better conditions.
Why it matters for longevity. Chronic low-grade inflammation is one of the twelve hallmarks of aging and a shared mechanism across cardiovascular disease, diabetes and cognitive decline. hs-CRP is the most accessible measure of it.
hs-CRP and Inflammation →Homocysteine calculator and dementia risk ranges
Enter your result to see the band. The association with risk is continuous rather than threshold-based, so read it as a gradient.
Why it matters for longevity. Each 5 micromol per liter increase is associated with roughly 50 percent higher dementia risk in pooled cohort data. Note the honest caveat: trials lowering it with B vitamins did not improve cognitive outcomes, so it is a risk signal rather than a proven lever.
Homocysteine →Cystatin C calculator and longevity ranges
A kidney marker that is not confounded by muscle mass, unlike creatinine. Particularly useful if you lift or supplement creatine, both of which can make creatinine look alarming when nothing is wrong.
Why it matters for longevity. Reduced kidney filtration is independently associated with cardiovascular events and all-cause mortality, and it progresses silently for years. Cystatin C catches earlier decline than creatinine, and is not distorted by muscle mass.
Cystatin C →Vitamin D calculator and optimal range
Enter your blood level in ng/mL. The bands run in both directions, so a very high result is flagged as well as a low one.
Why it matters for longevity. Deficiency is associated with poorer bone density, immune function and muscle strength, all of which bear on how well you age. The benefit lies in correcting a deficiency rather than pushing higher, which is why the band has a ceiling too.
Vitamin D3 →Omega-3 Index calculator and longevity ranges
Enter your Omega-3 Index result. Levels take three to four months to stabilize after a dose change, so retesting sooner measures a moving target.
Why it matters for longevity. A higher index is associated with lower cardiovascular mortality, and because it reflects red blood cell membranes it shows intake over months rather than what you ate this week. Only around one percent of Americans reach the desirable band.
The Omega-3 Index →GGT calculator and longevity ranges
Enter your GGT result in U/L. Retest at least 48 hours after alcohol, since this enzyme responds quickly to it.
Why it matters for longevity. Liver enzymes function as early metabolic stress markers, and elevated GGT is associated with cardiovascular and all-cause mortality beyond liver disease itself. Standard lab ranges call a doubled value normal.
Liver Enzymes: GGT and ALT →ALT calculator and longevity ranges
The other liver enzyme, more specific to liver cells but also present in muscle, so a hard training session in the days before a test can raise it.
Why it matters for longevity. Usually a signal of fat accumulating in the liver, which travels with insulin resistance and visceral fat. Non-alcoholic fatty liver disease affects roughly a quarter of adults and is largely reversible.
Liver Enzymes: GGT and ALT →TSH calculator and optimal range
Enter your TSH result to see it against both the standard laboratory range and the tighter optimal band.
Why it matters for longevity. Thyroid function sets metabolic rate and affects cardiovascular risk, cognition and body composition. Population levels drift upward with age, which is why a fixed reference range flags a growing share of older adults as abnormal.
Thyroid Function and Aging →Free T3 calculator and reference range
Enter your free T3 result. Most laboratories report in pg/mL, though some use pmol/L, which is a different scale entirely.
Why it matters for longevity. The active thyroid hormone, and the thinnest sourcing of anything tracked here, which the result says plainly. Like TSH, it is a medical marker rather than a lifestyle-responsive one.
Thyroid Function and Aging →You now have some numbers. What you don't have is an order.
Each of these tools answers one question in isolation. None of them tells you which one to fix first, and they don't carry equal weight: cardiovascular health is the single biggest lever on your overall score, with body composition behind it. A waist measurement and a VO2 Max figure are not equally urgent, and knowing both separately doesn't tell you that.
The Longevity Coach IQ app scores every tracked marker together, weights them, tells you which one to work on next, and shows whether it moved when you retest. No calculator can do that.