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Calcimator

Freeboard Calculator

Calculate minimum freeboard from load line regulations and compare against actual freeboard.

Inputs

ft
ft
ft

Results

Actual Freeboard

4 ft

≈ 8 smartphones

Minimum Freeboard2.8 ft
Margin1.2 ft
Reserve Buoyancy40%
How to Use This Calculator
  1. Enter the vessel's overall depth from keel to deck and the loaded draft in feet.
  2. Input vessel length and select the vessel type (Type A tanker or Type B general cargo).
  3. Review the actual freeboard (depth minus draft) and compare to the minimum freeboard.
  4. Check the reserve buoyancy percentage — higher values indicate more safety margin.
  5. If the margin is negative, reduce cargo load to achieve compliant freeboard.

How the result changes with Depth (Keel to Deck)

Depth (Keel to Deck)Actual Freeboard
1610 ft
5347 ft
9892 ft
135129 ft

What each input means

Depth (Keel to Deck)
Molded depth from keel to weather deck.
Loaded Draft
Draft at maximum loaded condition.
Vessel Length
Length for load line purposes.
Vessel Type
Type A vessels have lower minimum freeboard requirements.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Depth (Keel to Deck) = 10, Loaded Draft = 6, Vessel Length = 80, Vessel Type = 0 = 4 input(s) provided
  2. Calculate Actual Freeboard
    Actual Freeboard
    4 = 4
  3. Calculate Minimum Freeboard
    Minimum Freeboard
    2.8 = 2.8
  4. Calculate Margin
    Margin
    1.2 = 1.2

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