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Instrument catalog21 active tools

Measure first. Adjust next.

A workbench of calculators and tests to turn your sleep, nutrition, stress and performance data into clearer decisions.

Choose an instrument
One signal, one instrument, one verifiable decision.

Stacky

Six questions are enough to match your goal, budget, sensitivity and current routine. Stacky filters the options, limits the results and explains what it keeps.

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Stacky turns six answers into a short routine with clear reasoning.

Choose the instrument based on the signal to measure.

Each tool provides a targeted reference point and documents its limitations on its page.

21 tools divided into 6 families

Nutrition

Quantify intake, proportions and the balance of your meals.

7 tools
Active NutritionGlycemic index and glycemic loadCalculate the actual impact of your meals on blood sugar using glycemic index, glycemic load and adjustable portions. Open instrument Active NutritionHydration calculatorEstimate how much water to drink per day based on your weight, activity, heat and sweating. Open instrument Active NutritionOmega-3/omega-6 ratioCalculate your meal's omega-3/omega-6 ratio to better balance your fat intake. Open instrument Active NutritionProtein calculatorCalculate your daily protein needs based on your weight, activity and goal. Open instrument Active NutritionLeucine thresholdCalculate how much protein to aim for per meal to exceed the leucine threshold based on your goal and protein source. Open instrument Active NutritionFiber and bowel regularity scoreEstimate your fiber intake, your risk of sluggish bowel transit and the most useful adjustments. Open instrument Active NutritionCalorie deficit calculatorEstimate a moderate deficit, then compare the calculation with your actual weight trend over 14 to 21 days. Open instrument

Performance

Turn simple measurements into practical training zones.

4 tools
Active PerformanceElectrolytes and sweat rateMeasure your sweat rate and estimate your sodium, salt and fluid needs to recover better after exercise. Open instrument Active PerformanceBody compositionEstimate your body fat, lean mass, FFMI and target weight from your body measurements. Open instrument Active PerformanceHeart rate zone calculatorCalculate your heart rate zones to find your zone 2 and calibrate your intensity levels. Open instrument Active PerformanceSteps → km and time converterConvert your steps into kilometres, walking time and estimated calories based on your height and cadence. Open instrument

Stress & Recovery

Monitor the load and guide the return to a more stable state.

2 tools
Active Stress & RecoveryFree cardiac coherenceGuided 3-6-5 breathing to reduce stress, activate the vagus nerve and restore a more stable breathing rhythm. Open instrument Active Stress & RecoveryAllostatic stress scoreAssess your chronic stress level and allostatic load in 2 minutes. Open instrument

Supplements

Calibrate a dose or check whether a routine makes sense.

4 tools
Active SupplementsCreatine calculatorCalculate your creatine monohydrate dose, loading phase, maintenance dose and monthly cost. Open instrument Active SupplementsMagnesium: symptom reviewOrganize your observations with a non-validated questionnaire, without diagnosing a deficiency. Open instrument Active SupplementsCaffeine calculatorCalculate your ideal caffeine dose based on your weight, tolerance and CYP1A2 metabolism. Open instrument Active SupplementsSupplement stack interactionsCheck the compatibility of your supplement stack, spot overlaps and identify combinations to monitor. Open instrument

Longevity

Put composite markers in perspective without confusing them with a diagnosis.

1 instrument
Active LongevityPhenoAge calculatorEstimate your phenotypic age from nine blood markers with transparent conversion of French units. Open instrument

Sleep

Align your schedule, sleep quality and circadian rhythm.

3 tools
Active SleepSleep windowEstimate times using scenarios of 7, 8 and 9 hours of sleep, without predicting cycles. Open instrument Active SleepChronotype testDiscover your chronotype in 2 minutes to align your sleep, productivity and energy. Open instrument Active SleepSleep analyzerAnalyze your sleep quality in 2 minutes with a personalized score. Open instrument