Caffeine Half-Life Clearance at Bedtime & Ergogenic Pre-Workout Dose (3–6 mg/kg) Calculator

Track residual mg of caffeine at bedtime and find your latest "caffeine curfew" hour.

Active Caffeine Remaining at Bedtime
57.43 mg
Hours Needed to Clear Below 50 mg 10 hours
ISSN Ergogenic Low Dose (3 mg/kg) 222 mg
ISSN Ergogenic High Dose (6 mg/kg) 444 mg
Inputs
⚡ Scenarios:
mg
Total caffeine consumed in milligrams (e.g., 95mg espresso, 200mg pre-workout).
hours
Hours elapsed between caffeine consumption and planned sleep.
hours
Caffeine elimination half-life (5.0 hrs average; 3–4h fast metabolizer, 7–8h slow).
kg
Body weight in kg for ISSN 3–6 mg/kg ergogenic dosing range.
Results & Graph
Active Caffeine Remaining at Bedtime
57.43 mg
Hours Needed to Clear Below 50 mg
10 hours
ISSN Ergogenic Low Dose (3 mg/kg)
222 mg
ISSN Ergogenic High Dose (6 mg/kg)
444 mg

Active Caffeine Remaining at Bedtime

Graph 1 • Caffeine Half-Life & Bedtime • Domain Architecture & Live Telemetry Maps Caffeine Dose Consumed Mg, Hours Between Dose And Bedtime, Personal Half Life Hours through Caffeine Half-Life & Bedtime Formula.
Caffeine Half-Life & Bedtime • Clinical & Physiological Reference Scale Low / Baseline Target / Reference Elevated / Watch High / Action Active Caffeine Remaining at Bedtime: 57.43 mg Hours Needed to Clear Belo 10 hours ISSN Ergogenic Low Dose (3 222 mg ISSN Ergogenic High Dose ( 444 mg
Graph 2 • Active Caffeine Remaining at Bedtime Across Caffeine Dose Consumed Mg Sweep (40% → 160%) Evaluates RemainingCaffeine_mg = Dose_mg × (0.5)^(HoursUntilBedtime / HalfLife_hrs across 7 operating points (current input highlighted).
0 mg 50.55 mg 101.1 mg 22.97 80mg 34.46 120mg 45.95 160mg 57.43 200mg 68.92 240mg 80.41 280mg 91.90 320mg
Graph 3 • Joint Sensitivity: Caffeine Dose Consumed Mg × Hours Between Dose And Bedtime Compares Active Caffeine Remaining at Bedtime when Hours Between Dose And Bedtime is shifted +25% (solid) vs. −25% (dashed).
0 mg 56.10 mg 112.2 mg --- Hours Between Dose And Bedtime @ 75% 29.43 -30% 35.74 -15% 42.04 +0% 48.35 +15% 54.66 +30%
Summary: 9 hours after consuming 200 mg (half-life 5 hrs), 57.4 mg of active caffeine remains at bedtime (allow 10 hours before bed to drop below 50 mg).
Summary: 9 hours after consuming 200 mg (half-life 5 hrs), 57.4 mg of active caffeine remains at bedtime (allow 10 hours before bed to drop below 50 mg).
⚡ Send result to: BMI →Calorie & TDEE →Pace, 1RM & HR Zones →
Interactive chart & math engine powered by CalculatorGraph

Formula & Mathematical Methodology: Caffeine Half-Life & Bedtime Formula

RemainingCaffeinemg = Dosemg × (0.5)HoursUntilBedtime / HalfLifehrs
ErgogenicDose = 3 to 6 mg × Weightkg
RemainingCaffeine_mg = Dose_mg × (0.5)^(HoursUntilBedtime / HalfLife_hrs); ErgogenicDose = 3 to 6 mg × Weight_kg
  • caffeineDoseConsumedMg: Caffeine Dose Consumed Mg (mg)
  • hoursBetweenDoseAndBedtime: Hours Between Dose And Bedtime (hours)
  • personalHalfLifeHours: Personal Half Life Hours (hours)
  • bodyWeightKg: Body Weight Kg (kg)

Rounding: Clinical scores round to statutory integer or decimal precision; physiological metrics round to 2 decimal places.

Worked Example: Clinical / Physiology Scenario: Caffeine Half-Life & Bedtime

Track residual mg of caffeine at bedtime and find your latest "caffeine curfew" hour.

  1. Enter lab values, anthropometric measurements, or performance test metrics.
  2. Evaluate the reference equation: RemainingCaffeine_mg = Dose_mg × (0.5)^(HoursUntilBedtime / HalfLife_hrs); ErgogenicDose = 3 to 6 mg × Weight_kg.
  3. Inspect the primary classification, supporting indices, and 3 SVG charts.
Result: Computes Caffeine Half-Life & Bedtime via RemainingCaffeine_mg = Dose_mg × (0.5)^(HoursUntilBedtime / HalfLife_hrs); ErgogenicDose = 3 to 6 mg × Weight_kg.

Frequently Asked Questions

How does the Caffeine Half-Life Clearance at Bedtime & Ergogenic Pre-Workout Dose (3–6 mg/kg) Calculator compute its result?

It evaluates RemainingCaffeine_mg = Dose_mg × (0.5)^(HoursUntilBedtime / HalfLife_hrs); ErgogenicDose = 3 to 6 mg × Weight_kg directly in your browser and updates three custom SVG visualizations in real time.

Can I use Goal Seek to solve backwards for a target lab value or pace?

Yes. Click "🎯 Goal Seek" in the results toolbar to solve backwards for any numeric input parameter.

Are my health and biometric inputs kept private?

Yes. All calculations run 100% locally on your device with zero external transmission.

Health & Fitness · Sports Nutrition & Supplementation

Caffeine Half-Life Clearance at Bedtime & Ergogenic Pre-Workout Dose (3–6 mg/kg) Calculator: inputs, method, and how to read the result

Track residual mg of caffeine at bedtime and find your latest "caffeine curfew" hour.

Choose inputs for the case you are checking

The defaults are illustrative. Replace them with values for your case and keep the units shown beside each field.

  • Caffeine Dose Consumed Mg: Total caffeine consumed in milligrams (e.g., 95mg espresso, 200mg pre-workout).
  • Hours Between Dose And Bedtime: Hours elapsed between caffeine consumption and planned sleep.
  • Personal Half Life Hours: Caffeine elimination half-life (5.0 hrs average; 3–4h fast metabolizer, 7–8h slow).
  • Body Weight Kg: Body weight in kg for ISSN 3–6 mg/kg ergogenic dosing range.

What the calculation includes

With the default values shown, Active Caffeine Remaining at Bedtime is 57.43 mg. The calculation follows Caffeine Half-Life & Bedtime Formula; the formula and variable definitions above show how the inputs combine.

One-input check: With the other defaults held constant, changing Caffeine Dose Consumed Mg from 200 mg to 220 mg changes Active Caffeine Remaining at Bedtime from 57.43 mg to 63.18 mg. This is a comparison inside the calculator's stated model, not a prediction.

Where to use caution

  • Uses peer-reviewed clinical and sports physiology formulas.
  • For educational and informational reference only; clinical scores do not replace physician judgment or laboratory reference ranges.

Scope: Global Clinical & Sports Science Consensus Check the assumptions and limitations against your situation before relying on the estimate.

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