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Calcimator

Drying Room Calculator

Drying room capacity from harvest weight and rack spacing.

Inputs

%

Results

Expected dry weight (lbs)

25

Expected dry weight (oz)400
Water to remove (lbs)75
Required room (sq ft)200
Dehumidifiers needed1
Dehumidification (pints/day)6.3
Airflow needed (CFM)27
Adjusted drying days12
Hanging line needed (ft)100
Mold risk (1-3)1
Pints Per Hour0.26
Mold RiskLOW
How to Use This Calculator
  1. Enter wet harvest weight in lbs and select drying method (whole-plant hanging or rack/screen).
  2. Set target drying days, target relative humidity (%), and room temperature (°F).
  3. Review Expected Dry Weight (lbs), Room Required (sq ft), Dehumidifiers Needed, and Mold Risk Score.
  4. Keep RH below 60% and temperature at 60–65°F to slow-dry and preserve terpene profiles.

How the result changes with Wet harvest weight (lbs)

Wet harvest weight (lbs)Expected dry weight (lbs)
5,0001,250
17,5004,375
32,5008,125
45,00011,250

What each input means

Wet harvest weight (lbs)
Total wet (fresh-cut) harvest weight in pounds.
Drying method (0-1)
0 = Whole-plant hanging, 1 = Rack/screen drying.
Target drying days
Target number of days for the dry (10-14 is typical).
Target RH (%)
Target relative humidity. 55-62% is ideal for slow, quality drying.
Room temperature (°F)
Target room temperature. 60-65°F preserves terpenes.

What each result means

Expected dry weight (lbs)
Estimated final dry weight (~25% of wet weight).
Expected dry weight (oz)
Dry weight in ounces.
Water to remove (lbs)
Pounds of moisture that must evaporate.
Required room (sq ft)
Minimum room floor area needed.
Dehumidifiers needed
Number of 50-pint/day dehumidifier units.
Dehumidification (pints/day)
Required moisture removal capacity.
Airflow needed (CFM)
Minimum fan CFM for 1 air exchange per hour.
Adjusted drying days
Drying duration adjusted for temperature.
Hanging line needed (ft)
Linear feet of drying line (hanging method).
Mold risk (1-3)
1 = Low (<60% RH), 2 = Moderate (60-65%), 3 = High (>65%).

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Wet harvest weight (lbs) = 100, Drying method (0-1) = 0, Target drying days = 12, Target RH (%) = 60 = 5 input(s) provided
  2. Calculate Expected dry weight
    Expected dry weight = wetHarvestLbs * 0.25
    25 = 25
  3. Calculate Expected dry weight
    Expected dry weight = dryWeightLbs * 16
    400 = 400
  4. Calculate Water to remove
    Water to remove = wetHarvestLbs * 0.75
    75 = 75

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