EPK Readiness + Hydration Calculator

Compares your fixed 5-day Cronometer intake average to either estimated needs or Whoop totals. If Whoop is enabled and valid Whoop totals are entered, the calculator uses Whoop as the needs reference. If not, it uses estimated needs from RMR × PAL. It does not combine both. Status is then checked against fat percentage, so high energy driven by high fat intake does not automatically count as green or gold. At over 25% fat, effective status becomes amber. At over 35% fat, effective status becomes red. The ladder softens as intake approaches the constrained-energy ceiling, not simply because a traffic-light colour improves. For general populations, the ladder stops at 60 EPK. Only athlete mode can progress into the 80+ EPK range. It now also uses Cronometer energy and macro data to estimate hydration support from food water and metabolic water, then recommends the correct traffic-light exercise track.

Step 1: Your basic details (RMR)

Current body weight (kg)

Height (cm)

Age (years)

Sex

I already know my tested RMR (kcal/day)

Step 2: Activity level (PAL) including physical and mental strain

Choose the closest match

Mental strain counts because it increases recovery demand. If sleep is poor, stress is high, and you’re under-fuelled, your day often behaves like a higher PAL even if steps are modest.

Base re-expansion step size

This is the starting ladder step. The actual ladder softens automatically as intake approaches the constrained-energy ceiling.

Minimum hold per step

Fat cap for green/gold

If average fat intake is above this cap, effective status cannot become green or gold.

Constrained-energy ceiling profile

General ceiling is for typical non-athlete averages. Athlete ceiling allows progression into the 80+ EPK range before the ladder fully stops.

Amber fat intake threshold

At over 25% fat, effective status becomes amber.

Red fat intake threshold

At over 35% fat, effective status becomes red.

General soft / hard cap

For typical non-athlete averages, the ladder softens near 50 EPK and stops near 60 EPK.

Athlete soft / hard cap

Athlete mode is the only profile that allows the ladder to move into the 80+ EPK range.

Step 3: Fixed 5-day Cronometer input (total intake and macros in kcal)

I have a Whoop: use each day’s total Whoop calories as the needs reference

Enter each day’s total calories and macro calories from Cronometer (carb kcal, fat kcal, protein kcal). If Whoop is enabled, add that day’s total Whoop calories too. All 5 days are required. Days left blank or entered as 0 will stop the calculation so the result is always based on a true 5-day average.

If valid Whoop totals are entered for the days used, Whoop becomes the needs reference. If not, the calculator falls back to estimated needs from RMR × PAL.

Day 1

Total intake kcal

Carb kcal

Fat kcal

Protein kcal

Day 2

Total intake kcal

Carb kcal

Fat kcal

Protein kcal

Day 3

Total intake kcal

Carb kcal

Fat kcal

Protein kcal

Day 4

Total intake kcal

Carb kcal

Fat kcal

Protein kcal

Day 5

Total intake kcal

Carb kcal

Fat kcal

Protein kcal

Step 4: Biofeedback

These do not override the numbers, but they help place them in real physiology.

Warmer hands and feet

Falling asleep more easily

Deeper / more stable sleep

Calmer appetite / less food noise

Better mood / calmer nervous system

Better training recovery

Extra notes (optional)

Step 5: Hydration context

This section uses the Cronometer energy and macro data above. It estimates fluid support coming from food water and metabolic water, then suggests the remaining drinking-fluid range. It is not a medical fluid prescription.

Current drinking fluid (ml/day, optional)

Only drinks count here. The calculator estimates food/metabolic water separately.

Heat / sweat / training demand

Salt / electrolyte context

Summary

Your energy picture

RMR used

–

PAL

–

Base needs (RMR × PAL)

–

Avg Whoop total kcal

–

Needs source used

–

Needs used

–

5-day average intake

–

Intake vs needs used

–

EPK (intake)

–

EPK (needs-adjusted)

–

Energy tier (intake)

–

Effective status (intake)

–

Energy tier (needs-adjusted)

–

Effective status (needs-adjusted)

–

Dot 1 = intake energy position. Dot 2 = needs-adjusted position.

< 25
Red

25–30
Amber

30–35
Green

> 35
Gold

Fat % (kcal)

–

Carb % (kcal)

–

Protein % (kcal)

–

Visualise it

Intake vs needs

Shows average intake against estimated needs and the actual needs source used.

Macro split

Green and gold require fat to stay at or below your selected fat cap. Over 25% fat becomes amber. Over 35% fat becomes red.

Biofeedback

–

Hydration readiness

Energy-based fluid target

–

Estimated food water

–

Estimated metabolic water

–

Suggested drinking-fluid range

–

Current fluid vs range

–

Hydration interpretation

–

Exercise programme recommendation

Recommended track

–

Day-by-day

Shows daily intake against the needs reference used for that day.

Day	Intake	Whoop total	Needs used	Gap	EPK (intake)	EPK (needs-adjusted)

Zone Ladder

Ladder uses your current 5-day average intake as Step 0 and increases by your chosen base step size. As intake EPK approaches the constrained-energy ceiling, the ladder automatically softens and then stops. This is separate from the traffic-light label itself. Fat percentage can still slow or block progression. General mode stops at 60 EPK. Only athlete mode can move into the 80+ EPK range.

Step	Hold	Step size	Target intake	EPK (intake)	Energy tier	Effective status	EPK (needs-adjusted)	Effective status (needs-adjusted)	Notes

Send this to your coach

This opens your email app with the report included. If your email app truncates long messages, use Copy report and paste it into the email. Attach the downloaded PDF if you want a clean version. When the email opens, Billy is included so he receives a copy at billy@enerjarden.com.

Your name (optional)

Your email (used in the To field)

Report text (auto-filled after Calculate)

Gentle fat-rebalance suggestion (optional)

If fat % is high, the aim is a small, sustainable reduction in fat percentage while keeping protein stable and letting carbs rise.

Suggested fat % reduction step