Instruments
Measure the system you live in.
Most health calculators online cannot tell you where their numbers came from. Every tool here uses a published formula, names its source, and states plainly what it cannot tell you. They run entirely in your browser: nothing you enter is sent anywhere or stored.
Longevity signal
01Grip strength percentileEnter a hand dynamometer reading and see how it compares with published norms for your age and sex.2 minutes, once you have a dynamometer to hand↗
02VO2 max estimatorThree validated field methods: a one-mile walk, a resting heart-rate ratio, or a twelve-minute run.Under a minute to calculate, 12 to 20 minutes if you are doing the walk or run test↗
03Lifestyle ageNot a biological age clock. This applies the findings of a large cohort study to your answers and reports what it observed.About 2 minutes↗
Body composition
01
02Nutrition
01Energy and macrosMifflin-St Jeor for resting metabolism, an activity factor for daily burn, and a macronutrient split for your goal.About a minute↗
02Protein needsThe official minimum exists to prevent deficiency. The amount that supports muscle is considerably higher.Under a minute↗
03Meal plannerSet a target weight and a pace. Get a daily calorie and macronutrient target, a meal structure, and a timeline that does not flatter you.About 3 minutes↗
01Our standard
A number is only useful if you know what it means.
Sourced formulas
Every calculation names the study or guideline behind it. If we could not source it, we did not build it.
Stated limits
Each tool says what it cannot tell you, because a result you misread is worse than no result.
Nothing collected
Calculations run in your browser. Nothing you type is transmitted or stored.